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COLLECTD.CONF(5) collectd COLLECTD.CONF(5)

NAME
collectd.conf - Configuration for the system statistics collection daemon
collectd

SYNOPSIS
BaseDir "/var/db/collectd"
PIDFile "/run/collectd.pid"
Interval 10.0

LoadPlugin cpu
LoadPlugin load

<LoadPlugin df>
Interval 3600
</LoadPlugin>
<Plugin df>
ValuesPercentage true
</Plugin>

LoadPlugin ping
<Plugin ping>
Host "example.org"
Host "provider.net"
</Plugin>

DESCRIPTION
This config file controls how the system statistics collection daemon col-
lectd behaves. The most significant option is LoadPlugin, which controls
which plugins to load. These plugins ultimately define collectd's behavior.
If the AutoLoadPlugin option has been enabled, the explicit LoadPlugin
lines may be omitted for all plugins with a configuration block, i.e. a
"<Plugin ...>" block.

The syntax of this config file is similar to the config file of the famous
Apache webserver. Each line contains either an option (a key and a list of
one or more values) or a section-start or -end. Empty lines and everything
after a non-quoted hash-symbol ("#") are ignored. Keys are unquoted
strings, consisting only of alphanumeric characters and the underscore
("_") character. Keys are handled case insensitive by collectd itself and
all plugins included with it. Values can either be an unquoted string, a
quoted string (enclosed in double-quotes) a number or a boolean expression.
Unquoted strings consist of only alphanumeric characters and underscores
("_") and do not need to be quoted. Quoted strings are enclosed in double
quotes ("""). You can use the backslash character ("\") to include double
quotes as part of the string. Numbers can be specified in decimal and
floating point format (using a dot "." as decimal separator), hexadecimal
when using the "0x" prefix and octal with a leading zero (0). Boolean val-
ues are either true or false.

Lines may be wrapped by using "\" as the last character before the newline.
This allows long lines to be split into multiple lines. Quoted strings may
be wrapped as well. However, those are treated special in that whitespace
at the beginning of the following lines will be ignored, which allows for
nicely indenting the wrapped lines.

The configuration is read and processed in order, i.e. from top to bottom.
So the plugins are loaded in the order listed in this config file. It is a
good idea to load any logging plugins first in order to catch messages from
plugins during configuration. Also, unless AutoLoadPlugin is enabled, the
LoadPlugin option must occur before the appropriate "<Plugin ...>" block.

GLOBAL OPTIONS
BaseDir Directory
Sets the base directory. This is the directory beneath which all
RRD-files are created. Possibly more subdirectories are created. This
is also the working directory for the daemon.

LoadPlugin Plugin
Loads the plugin Plugin. This is required to load plugins, unless the
AutoLoadPlugin option is enabled (see below). Without any loaded plug-
ins, collectd will be mostly useless.

Only the first LoadPlugin statement or block for a given plugin name
has any effect. This is useful when you want to split up the configura-
tion into smaller files and want each file to be "self contained", i.e.
it contains a Plugin block and the appropriate LoadPlugin statement.
The downside is that if you have multiple conflicting LoadPlugin
blocks, e.g. when they specify different intervals, only one of them
(the first one encountered) will take effect and all others will be
silently ignored.

LoadPlugin may either be a simple configuration statement or a block
with additional options, affecting the behavior of LoadPlugin. A simple
statement looks like this:

LoadPlugin "cpu"

Options inside a LoadPlugin block can override default settings and in-
fluence the way plugins are loaded, e.g.:

<LoadPlugin perl>
Interval 60
</LoadPlugin>

The following options are valid inside LoadPlugin blocks:

Globals true|false
If enabled, collectd will export all global symbols of the plugin
(and of all libraries loaded as dependencies of the plugin) and,
thus, makes those symbols available for resolving unresolved sym-
bols in subsequently loaded plugins if that is supported by your
system.

This is useful (or possibly even required), e.g., when loading a
plugin that embeds some scripting language into the daemon (e.g.
the Perl and Python plugins). Scripting languages usually provide
means to load extensions written in C. Those extensions require
symbols provided by the interpreter, which is loaded as a depen-
dency of the respective collectd plugin. See the documentation of
those plugins (e.g., collectd-perl(5) or collectd-python(5)) for
details.

By default, this is disabled. As a special exception, if the plugin
name is either "perl" or "python", the default is changed to en-
abled in order to keep the average user from ever having to deal
with this low level linking stuff.

Interval Seconds
Sets a plugin-specific interval for collecting metrics. This over-
rides the global Interval setting. If a plugin provides its own
support for specifying an interval, that setting will take prece-
dence.

FlushInterval Seconds
Specifies the interval, in seconds, to call the flush callback if
it's defined in this plugin. By default, this is disabled.

FlushTimeout Seconds
Specifies the value of the timeout argument of the flush callback.

AutoLoadPlugin false|true
When set to false (the default), each plugin needs to be loaded explic-
itly, using the LoadPlugin statement documented above. If a <Plu-
gin ...> block is encountered and no configuration handling callback
for this plugin has been registered, a warning is logged and the block
is ignored.

When set to true, explicit LoadPlugin statements are not required. Each
<Plugin ...> block acts as if it was immediately preceded by a LoadPlu-
gin statement. LoadPlugin statements are still required for plugins
that don't provide any configuration, e.g. the Load plugin.

CollectInternalStats false|true
When set to true, various statistics about the collectd daemon will be
collected, with "collectd" as the plugin name. Defaults to false.

The following metrics are reported:

"collectd-write_queue/queue_length"
The number of metrics currently in the write queue. You can limit
the queue length with the WriteQueueLimitLow and WriteQueueLim-
itHigh options.

"collectd-write_queue/derive-dropped"
The number of metrics dropped due to a queue length limitation. If
this value is non-zero, your system can't handle all incoming met-
rics and protects itself against overload by dropping metrics.

"collectd-cache/cache_size"
The number of elements in the metric cache (the cache you can in-
teract with using collectd-unixsock(5)).

Include Path [pattern]
If Path points to a file, includes that file. If Path points to a di-
rectory, recursively includes all files within that directory and its
subdirectories. If the "wordexp" function is available on your system,
shell-like wildcards are expanded before files are included. This means
you can use statements like the following:

Include "/etc/collectd.d/*.conf"

Starting with version 5.3, this may also be a block in which further
options affecting the behavior of Include may be specified. The follow-
ing option is currently allowed:

<Include "/etc/collectd.d">
Filter "*.conf"
</Include>

Filter pattern
If the "fnmatch" function is available on your system, a shell-like
wildcard pattern may be specified to filter which files to include.
This may be used in combination with recursively including a direc-
tory to easily be able to arbitrarily mix configuration files and
other documents (e.g. README files). The given example is similar
to the first example above but includes all files matching "*.conf"
in any subdirectory of "/etc/collectd.d".

If more than one file is included by a single Include option, the files
will be included in lexicographical order (as defined by the "strcmp"
function). Thus, you can e. g. use numbered prefixes to specify the or-
der in which the files are loaded.

To prevent loops and shooting yourself in the foot in interesting ways
the nesting is limited to a depth of 8 levels, which should be suffi-
cient for most uses. Since symlinks are followed it is still possible
to crash the daemon by looping symlinks. In our opinion significant
stupidity should result in an appropriate amount of pain.

It is no problem to have a block like "<Plugin foo>" in more than one
file, but you cannot include files from within blocks.

PIDFile File
Sets where to write the PID file to. This file is overwritten when it
exists and deleted when the program is stopped. Some init-scripts might
override this setting using the -P command-line option.

PluginDir Directory
Path to the plugins (shared objects) of collectd.

TypesDB File [File ...]
Set one or more files that contain the data-set descriptions. See
types.db(5) for a description of the format of this file.

If this option is not specified, a default file is read. If you need to
define custom types in addition to the types defined in the default
file, you need to explicitly load both. In other words, if the TypesDB
option is encountered the default behavior is disabled and if you need
the default types you have to also explicitly load them.

Interval Seconds
Configures the interval in which to query the read plugins. Obviously
smaller values lead to a higher system load produced by collectd, while
higher values lead to more coarse statistics.

Warning: You should set this once and then never touch it again. If you
do, you will have to delete all your RRD files or know some serious
RRDtool magic! (Assuming you're using the RRDtool or RRDCacheD plugin.)

MaxReadInterval Seconds
A read plugin doubles the interval between queries after each failed
attempt to get data.

This options limits the maximum value of the interval. The default
value is 86400.

Timeout Iterations
Consider a value list "missing" when no update has been read or re-
ceived for Iterations iterations. By default, collectd considers a
value list missing when no update has been received for twice the up-
date interval. Since this setting uses iterations, the maximum allowed
time without update depends on the Interval information contained in
each value list. This is used in the Threshold configuration to dis-
patch notifications about missing values, see collectd-threshold(5) for
details.

ReadThreads Num
Number of threads to start for reading plugins. The default value is 5,
but you may want to increase this if you have more than five plugins
that take a long time to read. Mostly those are plugins that do net-
work-IO. Setting this to a value higher than the number of registered
read callbacks is not recommended.

WriteThreads Num
Number of threads to start for dispatching value lists to write plug-
ins. The default value is 5, but you may want to increase this if you
have more than five plugins that may take relatively long to write to.

WriteQueueLimitHigh HighNum
WriteQueueLimitLow LowNum
Metrics are read by the read threads and then put into a queue to be
handled by the write threads. If one of the write plugins is slow (e.g.
network timeouts, I/O saturation of the disk) this queue will grow. In
order to avoid running into memory issues in such a case, you can limit
the size of this queue.

By default, there is no limit and memory may grow indefinitely. This is
most likely not an issue for clients, i.e. instances that only handle
the local metrics. For servers it is recommended to set this to a
non-zero value, though.

You can set the limits using WriteQueueLimitHigh and WriteQueueLimit-
Low. Each of them takes a numerical argument which is the number of
metrics in the queue. If there are HighNum metrics in the queue, any
new metrics will be dropped. If there are less than LowNum metrics in
the queue, all new metrics will be enqueued. If the number of metrics
currently in the queue is between LowNum and HighNum, the metric is
dropped with a probability that is proportional to the number of met-
rics in the queue (i.e. it increases linearly until it reaches 100%.)

If WriteQueueLimitHigh is set to non-zero and WriteQueueLimitLow is un-
set, the latter will default to half of WriteQueueLimitHigh.

If you do not want to randomly drop values when the queue size is be-
tween LowNum and HighNum, set WriteQueueLimitHigh and WriteQueueLimit-
Low to the same value.

Enabling the CollectInternalStats option is of great help to figure out
the values to set WriteQueueLimitHigh and WriteQueueLimitLow to.

Hostname Name
Sets the hostname that identifies a host. If you omit this setting, the
hostname will be determined using the gethostname(2) system call.

FQDNLookup true|false
If Hostname is determined automatically this setting controls whether
or not the daemon should try to figure out the "fully qualified domain
name", FQDN. This is done using a lookup of the name returned by
"gethostname". This option is enabled by default.

PreCacheChain ChainName
PostCacheChain ChainName
Configure the name of the "pre-cache chain" and the "post-cache chain".
Please see "FILTER CONFIGURATION" below on information on chains and
how these setting change the daemon's behavior.

PLUGIN OPTIONS
Some plugins may register own options. These options must be enclosed in a
"Plugin"-Section. Which options exist depends on the plugin used. Some plu-
gins require external configuration, too. The "apache plugin", for example,
required "mod_status" to be configured in the webserver you're going to
collect data from. These plugins are listed below as well, even if they
don't require any configuration within collectd's configuration file.

A list of all plugins and a short summary for each plugin can be found in
the README file shipped with the sourcecode and hopefully binary packets as
well.

Plugin "aggregation"
The Aggregation plugin makes it possible to aggregate several values into
one using aggregation functions such as sum, average, min and max. This
can be put to a wide variety of uses, e.g. average and total CPU statistics
for your entire fleet.

The grouping is powerful but, as with many powerful tools, may be a bit
difficult to wrap your head around. The grouping will therefore be demon-
strated using an example: The average and sum of the CPU usage across all
CPUs of each host is to be calculated.

To select all the affected values for our example, set "Plugin cpu" and
"Type cpu". The other values are left unspecified, meaning "all values".
The Host, Plugin, PluginInstance, Type and TypeInstance options work as if
they were specified in the "WHERE" clause of an "SELECT" SQL statement.

Plugin "cpu"
Type "cpu"

Although the Host, PluginInstance (CPU number, i.e. 0, 1, 2, ...) and
TypeInstance (idle, user, system, ...) fields are left unspecified in the
example, the intention is to have a new value for each host / type instance
pair. This is achieved by "grouping" the values using the "GroupBy" option.
It can be specified multiple times to group by more than one field.

GroupBy "Host"
GroupBy "TypeInstance"

We do neither specify nor group by plugin instance (the CPU number), so all
metrics that differ in the CPU number only will be aggregated. Each aggre-
gation needs at least one such field, otherwise no aggregation would take
place.

The full example configuration looks like this:

<Plugin "aggregation">
<Aggregation>
Plugin "cpu"
Type "cpu"

GroupBy "Host"
GroupBy "TypeInstance"

CalculateSum true
CalculateAverage true
</Aggregation>
</Plugin>

There are a couple of limitations you should be aware of:

* The Type cannot be left unspecified, because it is not reasonable to
add apples to oranges. Also, the internal lookup structure won't work
if you try to group by type.

* There must be at least one unspecified, ungrouped field. Otherwise
nothing will be aggregated.

As you can see in the example above, each aggregation has its own Aggrega-
tion block. You can have multiple aggregation blocks and aggregation blocks
may match the same values, i.e. one value list can update multiple aggrega-
tions. The following options are valid inside Aggregation blocks:

Host Host
Plugin Plugin
PluginInstance PluginInstance
Type Type
TypeInstance TypeInstance
Selects the value lists to be added to this aggregation. Type must be a
valid data set name, see types.db(5) for details.

If the string starts with and ends with a slash ("/"), the string is
interpreted as a regular expression. The regex flavor used are POSIX
extended regular expressions as described in regex(7). Example usage:

Host "/^db[0-9]\\.example\\.com$/"

GroupBy Host|Plugin|PluginInstance|TypeInstance
Group valued by the specified field. The GroupBy option may be repeated
to group by multiple fields.

SetHost Host
SetPlugin Plugin
SetPluginInstance PluginInstance
SetTypeInstance TypeInstance
Sets the appropriate part of the identifier to the provided string.

The PluginInstance should include the placeholder "%{aggregation}"
which will be replaced with the aggregation function, e.g. "average".
Not including the placeholder will result in duplication warnings
and/or messed up values if more than one aggregation function are en-
abled.

The following example calculates the average usage of all "even" CPUs:

<Plugin "aggregation">
<Aggregation>
Plugin "cpu"
PluginInstance "/[0,2,4,6,8]$/"
Type "cpu"

SetPlugin "cpu"
SetPluginInstance "even-%{aggregation}"

GroupBy "Host"
GroupBy "TypeInstance"

CalculateAverage true
</Aggregation>
</Plugin>

This will create the files:

* foo.example.com/cpu-even-average/cpu-idle

* foo.example.com/cpu-even-average/cpu-system

* foo.example.com/cpu-even-average/cpu-user

* ...

CalculateNum true|false
CalculateSum true|false
CalculateAverage true|false
CalculateMinimum true|false
CalculateMaximum true|false
CalculateStddev true|false
Boolean options for enabling calculation of the number of value lists,
their sum, average, minimum, maximum and / or standard deviation. All
options are disabled by default.

Plugin "amqp"
The AMQP plugin can be used to communicate with other instances of collectd
or third party applications using an AMQP 0.9.1 message broker. Values are
sent to or received from the broker, which handles routing, queueing and
possibly filtering out messages.

Synopsis:

<Plugin "amqp">
# Send values to an AMQP broker
<Publish "some_name">
Host "localhost"
Host "fallback-amqp.example.com"
Port "5672"
VHost "/"
User "guest"
Password "guest"
Exchange "amq.fanout"
# ExchangeType "fanout"
# RoutingKey "collectd"
# Persistent false
# ConnectionRetryDelay 0
# Format "command"
# StoreRates false
# TLSEnabled false
# TLSVerifyPeer true
# TLSVerifyHostName true
# TLSCACert "/path/to/ca.pem"
# TLSClientCert "/path/to/client-cert.pem"
# TLSClientKey "/path/to/client-key.pem"
# GraphitePrefix "collectd."
# GraphiteEscapeChar "_"
# GraphiteSeparateInstances false
# GraphiteAlwaysAppendDS false
# GraphitePreserveSeparator false
</Publish>

# Receive values from an AMQP broker
<Subscribe "some_name">
Host "localhost"
Port "5672"
VHost "/"
User "guest"
Password "guest"
Exchange "amq.fanout"
# ExchangeType "fanout"
# Queue "queue_name"
# QueueDurable false
# QueueAutoDelete true
# RoutingKey "collectd.#"
# ConnectionRetryDelay 0
# TLSEnabled false
# TLSVerifyPeer true
# TLSVerifyHostName true
# TLSCACert "/path/to/ca.pem"
# TLSClientCert "/path/to/client-cert.pem"
# TLSClientKey "/path/to/client-key.pem"
</Subscribe>
</Plugin>

The plugin's configuration consists of a number of Publish and Subscribe
blocks, which configure sending and receiving of values respectively. The
two blocks are very similar, so unless otherwise noted, an option can be
used in either block. The name given in the blocks starting tag is only
used for reporting messages, but may be used to support flushing of certain
Publish blocks in the future.

Host Host [Host ...]
Hostname or IP-address of the AMQP broker. Defaults to the default be-
havior of the underlying communications library, rabbitmq-c, which is
"localhost".

If multiple hosts are specified, then a random one is chosen at each
(re)connection attempt. This is useful for failover with a clustered
broker.

Port Port
Service name or port number on which the AMQP broker accepts connec-
tions. This argument must be a string, even if the numeric form is
used. Defaults to "5672".

VHost VHost
Name of the virtual host on the AMQP broker to use. Defaults to "/".

User User
Password Password
Credentials used to authenticate to the AMQP broker. By default
"guest"/"guest" is used.

Exchange Exchange
In Publish blocks, this option specifies the exchange to send values
to. By default, "amq.fanout" will be used.

In Subscribe blocks this option is optional. If given, a binding be-
tween the given exchange and the queue is created, using the routing
key if configured. See the Queue and RoutingKey options below.

ExchangeType Type
If given, the plugin will try to create the configured exchange with
this type after connecting. When in a Subscribe block, the queue will
then be bound to this exchange.

Queue Queue (Subscribe only)
Configures the queue name to subscribe to. If no queue name was config-
ured explicitly, a unique queue name will be created by the broker.

QueueDurable true|false (Subscribe only)
Defines if the queue subscribed to is durable (saved to persistent
storage) or transient (will disappear if the AMQP broker is restarted).
Defaults to "false".

This option should be used in conjunction with the Persistent option on
the publish side.

QueueAutoDelete true|false (Subscribe only)
Defines if the queue subscribed to will be deleted once the last con-
sumer unsubscribes. Defaults to "true".

RoutingKey Key
In Publish blocks, this configures the routing key to set on all outgo-
ing messages. If not given, the routing key will be computed from the
identifier of the value. The host, plugin, type and the two instances
are concatenated together using dots as the separator and all contain-
ing dots replaced with slashes. For example "collectd.host/exam-
ple/com.cpu.0.cpu.user". This makes it possible to receive only spe-
cific values using a "topic" exchange.

In Subscribe blocks, configures the routing key used when creating a
binding between an exchange and the queue. The usual wildcards can be
used to filter messages when using a "topic" exchange. If you're only
interested in CPU statistics, you could use the routing key "col-
lectd.*.cpu.#" for example.

Persistent true|false (Publish only)
Selects the delivery method to use. If set to true, the persistent mode
will be used, i.e. delivery is guaranteed. If set to false (the de-
fault), the transient delivery mode will be used, i.e. messages may be
lost due to high load, overflowing queues or similar issues.

ConnectionRetryDelay Delay
When the connection to the AMQP broker is lost, defines the time in
seconds to wait before attempting to reconnect. Defaults to 0, which
implies collectd will attempt to reconnect at each read interval (in
Subscribe mode) or each time values are ready for submission (in Pub-
lish mode).

Format Command|JSON|Graphite (Publish only)
Selects the format in which messages are sent to the broker. If set to
Command (the default), values are sent as "PUTVAL" commands which are
identical to the syntax used by the Exec and UnixSock plugins. In this
case, the "Content-Type" header field will be set to "text/collectd".

If set to JSON, the values are encoded in the JavaScript Object Nota-
tion, an easy and straight forward exchange format. The "Content-Type"
header field will be set to "application/json".

If set to Graphite, values are encoded in the Graphite format, which is
"<metric> <value> <timestamp>\n". The "Content-Type" header field will
be set to "text/graphite".

A subscribing client should use the "Content-Type" header field to de-
termine how to decode the values. Currently, the AMQP plugin itself can
only decode the Command format.

StoreRates true|false (Publish only)
Determines whether or not "COUNTER", "DERIVE" and "ABSOLUTE" data
sources are converted to a rate (i.e. a "GAUGE" value). If set to false
(the default), no conversion is performed. Otherwise the conversion is
performed using the internal value cache.

Please note that currently this option is only used if the Format op-
tion has been set to JSON.

GraphitePrefix (Publish and Format=Graphite only)
A prefix can be added in the metric name when outputting in the
Graphite format. It's added before the Host name. Metric name will be
"<prefix><host><postfix><plugin><type><name>"

GraphitePostfix (Publish and Format=Graphite only)
A postfix can be added in the metric name when outputting in the
Graphite format. It's added after the Host name. Metric name will be
"<prefix><host><postfix><plugin><type><name>"

GraphiteEscapeChar (Publish and Format=Graphite only)
Specify a character to replace dots (.) in the host part of the metric
name. In Graphite metric name, dots are used as separators between
different metric parts (host, plugin, type). Default is "_" (Under-
score).

GraphiteSeparateInstances true|false
If set to true, the plugin instance and type instance will be in their
own path component, for example "host.cpu.0.cpu.idle". If set to false
(the default), the plugin and plugin instance (and likewise the type
and type instance) are put into one component, for example
"host.cpu-0.cpu-idle".

GraphiteAlwaysAppendDS true|false
If set to true, append the name of the Data Source (DS) to the "metric"
identifier. If set to false (the default), this is only done when there
is more than one DS.

GraphitePreserveSeparator false|true
If set to false (the default) the "." (dot) character is replaced with
GraphiteEscapeChar. Otherwise, if set to true, the "." (dot) character
is preserved, i.e. passed through.

TLSEnabled true|false
If set to true then connect to the broker using a TLS connection. If
set to false (the default), then a plain text connection is used.

Requires rabbitmq-c >= 0.4.

TLSVerifyPeer true|false
If set to true (the default) then the server certificate chain is veri-
fied. Setting this to false will skip verification (insecure).

Requires rabbitmq-c >= 0.8.

TLSVerifyHostName true|false
If set to true (the default) then the server host name is verified.
Setting this to false will skip verification (insecure).

Requires rabbitmq-c >= 0.8.

TLSCACert Path
Path to the CA cert file in PEM format.

TLSClientCert Path
Path to the client certificate in PEM format. If this is set, then
TLSClientKey must be set as well.

TLSClientKey Path
Path to the client key in PEM format. If this is set, then
TLSClientCert must be set as well.

Plugin "amqp1"
The AMQP1 plugin can be used to communicate with other instances of col-
lectd or third party applications using an AMQP 1.0 message intermediary.
Metric values or notifications are sent to the messaging intermediary which
may handle direct messaging or queue based transfer.

Synopsis:

<Plugin "amqp1">
# Send values to an AMQP 1.0 intermediary
<Transport "name">
Host "localhost"
Port "5672"
User "guest"
Password "guest"
Address "collectd"
# RetryDelay 1
<Instance "some_name">
Format "command"
PreSettle false
Notify false
# StoreRates false
# GraphitePrefix "collectd."
# GraphiteEscapeChar "_"
# GraphiteSeparateInstances false
# GraphiteAlwaysAppendDS false
# GraphitePreserveSeparator false
</Instance>
</Transport>
</Plugin>

The plugin's configuration consists of a Transport that configures communi-
cations to the AMQP 1.0 messaging bus and one or more Instance correspond-
ing to metric or event publishers to the messaging system.

The address in the Transport block concatenated with the name given in the
Instance block starting tag will be used as the send-to address for commu-
nications over the messaging link.

The following options are accepted within each Transport block:

Host Host
Hostname or IP-address of the AMQP 1.0 intermediary. Defaults to the
default behavior of the underlying communications library, libqpid-pro-
ton, which is "localhost".

Port Port
Service name or port number on which the AMQP 1.0 intermediary accepts
connections. This argument must be a string, even if the numeric form
is used. Defaults to "5672".

User User
Password Password
Credentials used to authenticate to the AMQP 1.0 intermediary. By de-
fault "guest"/"guest" is used.

Address Address
This option specifies the prefix for the send-to value in the message.
By default, "collectd" will be used.

RetryDelay RetryDelay
When the AMQP1 connection is lost, defines the time in seconds to wait
before attempting to reconnect. Defaults to 1, which implies attempt to
reconnect at 1 second intervals.

SendQueueLimit SendQueueLimit If there is no AMQP1 connection, the plugin
will continue to queue messages to send, which could result in unbounded
memory consumption. This parameter is used to limit the number of messages
in the outbound queue to the specified value. The default value is 0, which
disables this feature.

The following options are accepted within each Instance block:

Format Command|JSON|Graphite
Selects the format in which messages are sent to the intermediary. If
set to Command (the default), values are sent as "PUTVAL" commands
which are identical to the syntax used by the Exec and UnixSock plug-
ins. In this case, the "Content-Type" header field will be set to
"text/collectd".

If set to JSON, the values are encoded in the JavaScript Object Nota-
tion, an easy and straight forward exchange format. The "Content-Type"
header field will be set to "application/json".

If set to Graphite, values are encoded in the Graphite format, which is
"<metric> <value> <timestamp>\n". The "Content-Type" header field will
be set to "text/graphite".

A subscribing client should use the "Content-Type" header field to de-
termine how to decode the values.

PreSettle true|false
If set to false (the default), the plugin will wait for a message ac-
knowledgement from the messaging bus before sending the next message.
This indicates transfer of ownership to the messaging system. If set to
true, the plugin will not wait for a message acknowledgement and the
message may be dropped prior to transfer of ownership.

Notify true|false
If set to false (the default), the plugin will service the instance
write call back as a value list. If set to true the plugin will service
the instance as a write notification callback for alert formatting.

StoreRates true|false
Determines whether or not "COUNTER", "DERIVE" and "ABSOLUTE" data
sources are converted to a rate (i.e. a "GAUGE" value). If set to false
(the default), no conversion is performed. Otherwise the conversion is
performed using the internal value cache.

Please note that currently this option is only used if the Format op-
tion has been set to JSON.

GraphitePrefix
A prefix can be added in the metric name when outputting in the
Graphite format. It's added before the Host name. Metric name will be
"<prefix><host><postfix><plugin><type><name>"

GraphitePostfix
A postfix can be added in the metric name when outputting in the
Graphite format. It's added after the Host name. Metric name will be
"<prefix><host><postfix><plugin><type><name>"

GraphiteEscapeChar
Specify a character to replace dots (.) in the host part of the metric
name. In Graphite metric name, dots are used as separators between
different metric parts (host, plugin, type). Default is "_" (Under-
score).

GraphiteAlwaysAppendDS true|false
If set to true, append the name of the Data Source (DS) to the "metric"
identifier. If set to false (the default), this is only done when there
is more than one DS.

Plugin "apache"
To configure the "apache"-plugin you first need to configure the Apache
webserver correctly. The Apache-plugin "mod_status" needs to be loaded and
working and the "ExtendedStatus" directive needs to be enabled. You can use
the following snipped to base your Apache config upon:

ExtendedStatus on
<IfModule mod_status.c>
<Location /mod_status>
SetHandler server-status
</Location>
</IfModule>

Since its "mod_status" module is very similar to Apache's, lighttpd is also
supported. It introduces a new field, called "BusyServers", to count the
number of currently connected clients. This field is also supported.

The configuration of the Apache plugin consists of one or more "<In-
stance />" blocks. Each block requires one string argument as the instance
name. For example:

<Plugin "apache">
<Instance "www1">
URL "http://www1.example.com/mod_status?auto"
</Instance>
<Instance "www2">
URL "http://www2.example.com/mod_status?auto"
</Instance>
</Plugin>

The instance name will be used as the plugin instance. To emulate the old
(version 4) behavior, you can use an empty string (""). In order for the
plugin to work correctly, each instance name must be unique. This is not
enforced by the plugin and it is your responsibility to ensure it.

The following options are accepted within each Instance block:

URL http://host/mod_status?auto
Sets the URL of the "mod_status" output. This needs to be the output
generated by "ExtendedStatus on" and it needs to be the machine read-
able output generated by appending the "?auto" argument. This option is
mandatory.

User Username
Optional user name needed for authentication.

Password Password
Optional password needed for authentication.

VerifyPeer true|false
Enable or disable peer SSL certificate verification. See
<http://curl.haxx.se/docs/sslcerts.html> for details. Enabled by de-
fault.

VerifyHost true|false
Enable or disable peer host name verification. If enabled, the plugin
checks if the "Common Name" or a "Subject Alternate Name" field of the
SSL certificate matches the host name provided by the URL option. If
this identity check fails, the connection is aborted. Obviously, only
works when connecting to a SSL enabled server. Enabled by default.

CACert File
File that holds one or more SSL certificates. If you want to use HTTPS
you will possibly need this option. What CA certificates come bundled
with "libcurl" and are checked by default depends on the distribution
you use.

SSLCiphers list of ciphers
Specifies which ciphers to use in the connection. The list of ciphers
must specify valid ciphers. See <http://www.openssl.org/docs/apps/ci-
phers.html> for details.

Timeout Milliseconds
The Timeout option sets the overall timeout for HTTP requests to URL,
in milliseconds. By default, the configured Interval is used to set the
timeout.

Plugin "apcups"
Host Hostname
Hostname of the host running apcupsd. Defaults to localhost. Please
note that IPv6 support has been disabled unless someone can confirm or
decline that apcupsd can handle it.

Port Port
TCP-Port to connect to. Defaults to 3551.

ReportSeconds true|false
If set to true, the time reported in the "timeleft" metric will be con-
verted to seconds. This is the recommended setting. If set to false,
the default for backwards compatibility, the time will be reported in
minutes.

PersistentConnection true|false
The plugin is designed to keep the connection to apcupsd open between
reads. If plugin poll interval is greater than 15 seconds (hardcoded
socket close timeout in apcupsd NIS), then this option is false by de-
fault.

You can instruct the plugin to close the connection after each read by
setting this option to false or force keeping the connection by setting
it to true.

If apcupsd appears to close the connection due to inactivity quite
quickly, the plugin will try to detect this problem and switch to an
open-read-close mode.

Plugin "aquaero"
This plugin collects the value of the available sensors in an Aquaero 5
board. Aquaero 5 is a water-cooling controller board, manufactured by Aqua
Computer GmbH <http://www.aquacomputer.de/>, with a USB2 connection for
monitoring and configuration. The board can handle multiple temperature
sensors, fans, water pumps and water level sensors and adjust the output
settings such as fan voltage or power used by the water pump based on the
available inputs using a configurable controller included in the board.
This plugin collects all the available inputs as well as some of the output
values chosen by this controller. The plugin is based on the libaquaero5
library provided by aquatools-ng.

Device DevicePath
Device path of the Aquaero 5's USB HID (human interface device), usu-
ally in the form "/dev/usb/hiddevX". If this option is no set the plu-
gin will try to auto-detect the Aquaero 5 USB device based on vendor-ID
and product-ID.

Plugin "ascent"
This plugin collects information about an Ascent server, a free server for
the "World of Warcraft" game. This plugin gathers the information by fetch-
ing the XML status page using "libcurl" and parses it using "libxml2".

The configuration options are the same as for the "apache" plugin above:

URL http://localhost/ascent/status/
Sets the URL of the XML status output.

User Username
Optional user name needed for authentication.

Password Password
Optional password needed for authentication.

VerifyPeer true|false
Enable or disable peer SSL certificate verification. See
<http://curl.haxx.se/docs/sslcerts.html> for details. Enabled by de-
fault.

Timeout Milliseconds
The Timeout option sets the overall timeout for HTTP requests to URL,
in milliseconds. By default, the configured Interval is used to set the
timeout.

Plugin "barometer"
This plugin reads absolute air pressure using digital barometer sensor on a
I2C bus. Supported sensors are:

MPL115A2 from Freescale, see <http://www.freescale.com/we-
bapp/sps/site/prod_summary.jsp?code=MPL115A>.
MPL3115 from Freescale see <http://www.freescale.com/we-
bapp/sps/site/prod_summary.jsp?code=MPL3115A2>.
BMP085 from Bosch Sensortec

The sensor type - one of the above - is detected automatically by the plu-
gin and indicated in the plugin_instance (you will see subdirectory "barom-
eter-mpl115" or "barometer-mpl3115", or "barometer-bmp085"). The order of
detection is BMP085 -> MPL3115 -> MPL115A2, the first one found will be
used (only one sensor can be used by the plugin).

The plugin provides absolute barometric pressure, air pressure reduced to
sea level (several possible approximations) and as an auxiliary value also
internal sensor temperature. It uses (expects/provides) typical metric
units - pressure in [hPa], temperature in [C], altitude in [m].

It was developed and tested under Linux only. The only platform dependency
is the standard Linux i2c-dev interface (the particular bus driver has to
support the SM Bus command subset).

The reduction or normalization to mean sea level pressure requires (depend-
ing on selected method/approximation) also altitude and reference to tem-
perature sensor(s). When multiple temperature sensors are configured the
minimum of their values is always used (expecting that the warmer ones are
affected by e.g. direct sun light at that moment).

Synopsis:

<Plugin "barometer">
Device "/dev/i2c-0";
Oversampling 512
PressureOffset 0.0
TemperatureOffset 0.0
Normalization 2
Altitude 238.0
TemperatureSensor "myserver/onewire-F10FCA000800/temperature"
</Plugin>

Device device
The only mandatory configuration parameter.

Device name of the I2C bus to which the sensor is connected. Note that
typically you need to have loaded the i2c-dev module. Using i2c-tools
you can check/list i2c buses available on your system by:

i2cdetect -l

Then you can scan for devices on given bus. E.g. to scan the whole bus
0 use:

i2cdetect -y -a 0

This way you should be able to verify that the pressure sensor (either
type) is connected and detected on address 0x60.

Oversampling value
Optional parameter controlling the oversampling/accuracy. Default value
is 1 providing fastest and least accurate reading.

For MPL115 this is the size of the averaging window. To filter out sen-
sor noise a simple averaging using floating window of this configurable
size is used. The plugin will use average of the last "value" measure-
ments (value of 1 means no averaging). Minimal size is 1, maximal
1024.

For MPL3115 this is the oversampling value. The actual oversampling is
performed by the sensor and the higher value the higher accuracy and
longer conversion time (although nothing to worry about in the collectd
context). Supported values are: 1, 2, 4, 8, 16, 32, 64 and 128. Any
other value is adjusted by the plugin to the closest supported one.

For BMP085 this is the oversampling value. The actual oversampling is
performed by the sensor and the higher value the higher accuracy and
longer conversion time (although nothing to worry about in the collectd
context). Supported values are: 1, 2, 4, 8. Any other value is ad-
justed by the plugin to the closest supported one.

PressureOffset offset
Optional parameter for MPL3115 only.

You can further calibrate the sensor by supplying pressure and/or tem-
perature offsets. This is added to the measured/caclulated value (i.e.
if the measured value is too high then use negative offset). In hPa,
default is 0.0.

TemperatureOffset offset
Optional parameter for MPL3115 only.

Normalization method
Optional parameter, default value is 0.

Normalization method - what approximation/model is used to compute the
mean sea level pressure from the air absolute pressure.

Supported values of the "method" (integer between from 0 to 2) are:

0 - no conversion, absolute pressure is simply copied over. For this
method you do not need to configure "Altitude" or "TemperatureSensor".
1 - international formula for conversion , See
<http://en.wikipedia.org/wiki/Atmospheric_pressure#Altitude_atmos-
pheric_pressure_variation>. For this method you have to configure "Al-
titude" but do not need "TemperatureSensor" (uses fixed global tempera-
ture average instead).
2 - formula as recommended by the Deutsche Wetterdienst (German Meteo-
rological Service). See
<http://de.wikipedia.org/wiki/Barometrische_H%C3%B6henformel#Theorie>
For this method you have to configure both "Altitude" and "Tempera-
tureSensor".

Altitude altitude
The altitude (in meters) of the location where you meassure the pres-
sure.

TemperatureSensor reference
Temperature sensor(s) which should be used as a reference when normal-
izing the pressure using "Normalization" method 2. When specified more
sensors a minimum is found and used each time. The temperature reading
directly from this pressure sensor/plugin is typically not suitable as
the pressure sensor will be probably inside while we want outside tem-
perature. The collectd reference name is something like <host-
name>/<plugin_name>-<plugin_instance>/<type>-<type_instance> (<type_in-
stance> is usually omitted when there is just single value type). Or
you can figure it out from the path of the output data files.

Plugin "battery"
The battery plugin reports the remaining capacity, power and voltage of
laptop batteries.

ValuesPercentage false|true
When enabled, remaining capacity is reported as a percentage, e.g. "42%
capacity remaining". Otherwise the capacity is stored as reported by
the battery, most likely in "Wh". This option does not work with all
input methods, in particular when only "/proc/pmu" is available on an
old Linux system. Defaults to false.

ReportDegraded false|true
Typical laptop batteries degrade over time, meaning the capacity de-
creases with recharge cycles. The maximum charge of the previous charge
cycle is tracked as "last full capacity" and used to determine that a
battery is "fully charged".

When this option is set to false, the default, the battery plugin will
only report the remaining capacity. If the ValuesPercentage option is
enabled, the relative remaining capacity is calculated as the ratio of
the "remaining capacity" and the "last full capacity". This is what
most tools, such as the status bar of desktop environments, also do.

When set to true, the battery plugin will report three values: charged
(remaining capacity), discharged (difference between "last full capac-
ity" and "remaining capacity") and degraded (difference between "design
capacity" and "last full capacity").

QueryStateFS false|true
When set to true, the battery plugin will only read statistics related
to battery performance as exposed by StateFS at /run/state. StateFS is
used in Mer-based Sailfish OS, for example.

Plugin "bind"
Starting with BIND 9.5.0, the most widely used DNS server software provides
extensive statistics about queries, responses and lots of other informa-
tion. The bind plugin retrieves this information that's encoded in XML and
provided via HTTP and submits the values to collectd.

To use this plugin, you first need to tell BIND to make this information
available. This is done with the "statistics-channels" configuration op-
tion:

statistics-channels {
inet localhost port 8053;
};

The configuration follows the grouping that can be seen when looking at the
data with an XSLT compatible viewer, such as a modern web browser. It's
probably a good idea to make yourself familiar with the provided values, so
you can understand what the collected statistics actually mean.

Synopsis:

<Plugin "bind">
URL "http://localhost:8053/"
ParseTime false
OpCodes true
QTypes true

ServerStats true
ZoneMaintStats true
ResolverStats false
MemoryStats true

<View "_default">
QTypes true
ResolverStats true
CacheRRSets true

Zone "127.in-addr.arpa/IN"
</View>
</Plugin>

The bind plugin accepts the following configuration options:

URL URL
URL from which to retrieve the XML data. If not specified, "http://lo-
calhost:8053/" will be used.

ParseTime true|false
When set to true, the time provided by BIND will be parsed and used to
dispatch the values. When set to false, the local time source is
queried.

This setting is set to true by default for backwards compatibility;
setting this to false is recommended to avoid problems with timezones
and localization.

OpCodes true|false
When enabled, statistics about the "OpCodes", for example the number of
"QUERY" packets, are collected.

Default: Enabled.

QTypes true|false
When enabled, the number of incoming queries by query types (for exam-
ple "A", "MX", "AAAA") is collected.

Default: Enabled.

ServerStats true|false
Collect global server statistics, such as requests received over IPv4
and IPv6, successful queries, and failed updates.

Default: Enabled.

ZoneMaintStats true|false
Collect zone maintenance statistics, mostly information about notifica-
tions (zone updates) and zone transfers.

Default: Enabled.

ResolverStats true|false
Collect resolver statistics, i. e. statistics about outgoing requests
(e. g. queries over IPv4, lame servers). Since the global resolver
counters apparently were removed in BIND 9.5.1 and 9.6.0, this is dis-
abled by default. Use the ResolverStats option within a View "_default"
block instead for the same functionality.

Default: Disabled.

MemoryStats
Collect global memory statistics.

Default: Enabled.

Timeout Milliseconds
The Timeout option sets the overall timeout for HTTP requests to URL,
in milliseconds. By default, the configured Interval is used to set the
timeout.

View Name
Collect statistics about a specific "view". BIND can behave different,
mostly depending on the source IP-address of the request. These differ-
ent configurations are called "views". If you don't use this feature,
you most likely are only interested in the "_default" view.

Within a <View name> block, you can specify which information you want
to collect about a view. If no View block is configured, no detailed
view statistics will be collected.

QTypes true|false
If enabled, the number of outgoing queries by query type (e. g.
"A", "MX") is collected.

Default: Enabled.

ResolverStats true|false
Collect resolver statistics, i. e. statistics about outgoing re-
quests (e. g. queries over IPv4, lame servers).

Default: Enabled.

CacheRRSets true|false
If enabled, the number of entries ("RR sets") in the view's cache
by query type is collected. Negative entries (queries which re-
sulted in an error, for example names that do not exist) are re-
ported with a leading exclamation mark, e. g. "!A".

Default: Enabled.

Zone Name
When given, collect detailed information about the given zone in
the view. The information collected if very similar to the global
ServerStats information (see above).

You can repeat this option to collect detailed information about
multiple zones.

By default no detailed zone information is collected.

Plugin "buddyinfo"
The buddyinfo plugin collects information by reading "/proc/buddyinfo".
This file contains information about the number of available contagious
physical pages at the moment.

Zone ZoneName
Zone to collect info about. Will collect all zones by default.

Plugin "capabilities"
The "capabilities" plugin collects selected static platform data using
dmidecode and expose it through micro embedded webserver. The data returned
by plugin is in json format.

Synopsis:

<Plugin capabilities>
Host "localhost"
Port "9104"
</Plugin>

Available configuration options for the "capabilities" plugin:

Host Hostname
Bind to the hostname / address Host. By default, the plugin will bind
to the "any" address, i.e. accept packets sent to any of the hosts ad-
dresses.

This option is supported only for libmicrohttpd newer than 0.9.0.

Port Port
Port the embedded webserver should listen on. Defaults to 9104.

Plugin "ceph"
The ceph plugin collects values from JSON data to be parsed by libyajl
(<https://lloyd.github.io/yajl/>) retrieved from ceph daemon admin sockets.

A separate Daemon block must be configured for each ceph daemon to be moni-
tored. The following example will read daemon statistics from four separate
ceph daemons running on the same device (two OSDs, one MON, one MDS) :

<Plugin ceph>
LongRunAvgLatency false
ConvertSpecialMetricTypes true
<Daemon "osd.0">
SocketPath "/var/run/ceph/ceph-osd.0.asok"
</Daemon>
<Daemon "osd.1">
SocketPath "/var/run/ceph/ceph-osd.1.asok"
</Daemon>
<Daemon "mon.a">
SocketPath "/var/run/ceph/ceph-mon.ceph1.asok"
</Daemon>
<Daemon "mds.a">
SocketPath "/var/run/ceph/ceph-mds.ceph1.asok"
</Daemon>
</Plugin>

The ceph plugin accepts the following configuration options:

LongRunAvgLatency true|false
If enabled, latency values(sum,count pairs) are calculated as the long
run average - average since the ceph daemon was started = (sum /
count). When disabled, latency values are calculated as the average
since the last collection = (sum_now - sum_last) / (count_now -
count_last).

Default: Disabled

ConvertSpecialMetricTypes true|false
If enabled, special metrics (metrics that differ in type from similar
counters) are converted to the type of those similar counters. This
currently only applies to filestore.journal_wr_bytes which is a counter
for OSD daemons. The ceph schema reports this metric type as a
sum,count pair while similar counters are treated as derive types. When
converted, the sum is used as the counter value and is treated as a de-
rive type. When disabled, all metrics are treated as the types re-
ceived from the ceph schema.

Default: Enabled

Each Daemon block must have a string argument for the plugin instance name.
A SocketPath is also required for each Daemon block:

Daemon DaemonName
Name to be used as the instance name for this daemon.

SocketPath SocketPath
Specifies the path to the UNIX admin socket of the ceph daemon.

Plugin "cgroups"
This plugin collects the CPU user/system time for each cgroup by reading
the cpuacct.stat files in the first cpuacct-mountpoint (typically
/sys/fs/cgroup/cpu.cpuacct on machines using systemd).

CGroup Directory
Select cgroup based on the name. Whether only matching cgroups are col-
lected or if they are ignored is controlled by the IgnoreSelected op-
tion; see below.

See /"IGNORELISTS" for details.

IgnoreSelected true|false
Invert the selection: If set to true, all cgroups except the ones that
match any one of the criteria are collected. By default only selected
cgroups are collected if a selection is made. If no selection is con-
figured at all, all cgroups are selected.

Plugin "check_uptime"
The check_uptime plugin designed to check and notify about host or service
status based on uptime metric.

When new metric of uptime type appears in cache, OK notification is sent.
When new value for metric is less than previous value, WARNING notification
is sent about host/service restart. When no new updates comes for metric
and cache entry expires, then FAILURE notification is sent about unreach-
able host or service.

By default (when no explicit configuration), plugin checks for uptime met-
ric.

Synopsis:

<Plugin "check_uptime">
Type "uptime"
Type "my_uptime_type"
</Plugin>

Type Type
Metric type to check for status/values. The type should consist single
GAUGE data source.

Plugin "chrony"
The "chrony" plugin collects ntp data from a chronyd server, such as clock
skew and per-peer stratum.

For talking to chronyd, it mimics what the chronyc control program does on
the wire.

Available configuration options for the "chrony" plugin:

Host Hostname
Hostname of the host running chronyd. Defaults to localhost.

Port Port
UDP-Port to connect to. Defaults to 323.

Timeout Timeout
Connection timeout in seconds. Defaults to 2.

Plugin Connectivity
connectivity - Documentation of collectd's "connectivity plugin"

LoadPlugin connectivity
# ...
<Plugin connectivity>
Interface eth0
</Plugin>

The "connectivity plugin" queries interface status using netlink (man 7
netlink) which provides information about network interfaces via the
NETLINK_ROUTE family (man 7 rtnetlink). The plugin translates the value it
receives to collectd's internal format and, depending on the write plugins
you have loaded, it may be written to disk or submitted to another in-
stance. The plugin listens to interfaces enumerated within the plugin con-
figuration (see below). If no interfaces are listed, then the default is
for all interfaces to be monitored.

This example shows "connectivity plugin" monitoring all interfaces. Load-
Plugin connectivity <Plugin connectivity> </Plugin>

This example shows "connectivity plugin" monitoring 2 interfaces, "eth0"
and "eth1". LoadPlugin connectivity <Plugin connectivity>
Interface eth0
Interface eth1 </Plugin>

This example shows "connectivity plugin" monitoring all interfaces except
"eth1". LoadPlugin connectivity <Plugin connectivity>
Interface eth1
IgnoreSelected true </Plugin>

Interface interface_name
interface(s) to monitor connect to.

Plugin "conntrack"
This plugin collects IP conntrack statistics.

OldFiles
Assume the conntrack_count and conntrack_max files to be found in
/proc/sys/net/ipv4/netfilter instead of /proc/sys/net/netfilter/.

Plugin "cpu"
The CPU plugin collects CPU usage metrics. By default, CPU usage is re-
ported as Jiffies, using the "cpu" type. Two aggregations are available:

* Sum, per-state, over all CPUs installed in the system; and

* Sum, per-CPU, over all non-idle states of a CPU, creating an "active"
state.

The two aggregations can be combined, leading to collectd only emitting a
single "active" metric for the entire system. As soon as one of these ag-
gregations (or both) is enabled, the cpu plugin will report a percentage,
rather than Jiffies. In addition, you can request individual, per-state,
per-CPU metrics to be reported as percentage.

The following configuration options are available:

ReportByState true|false
When set to true, the default, reports per-state metrics, e.g. "sys-
tem", "user" and "idle". When set to false, aggregates (sums) all
non-idle states into one "active" metric.

ReportByCpu true|false
When set to true, the default, reports per-CPU (per-core) metrics.
When set to false, instead of reporting metrics for individual CPUs,
only a global sum of CPU states is emitted.

ValuesPercentage false|true
This option is only considered when both, ReportByCpu and ReportByState
are set to true. In this case, by default, metrics will be reported as
Jiffies. By setting this option to true, you can request percentage
values in the un-aggregated (per-CPU, per-state) mode as well.

ReportNumCpu false|true
When set to true, reports the number of available CPUs. Defaults to
false.

ReportGuestState false|true
When set to true, reports the "guest" and "guest_nice" CPU states. De-
faults to false.

SubtractGuestState false|true
This option is only considered when ReportGuestState is set to true.
"guest" and "guest_nice" are included in respectively "user" and
"nice". If set to true, "guest" will be subtracted from "user" and
"guest_nice" will be subtracted from "nice". Defaults to true.

Plugin "cpufreq"
This plugin is available on Linux and FreeBSD only. It doesn't have any
options. On Linux it reads /sys/devices/system/cpu/cpu0/cpufreq/scal-
ing_cur_freq (for the first CPU installed) to get the current CPU fre-
quency. If this file does not exist make sure cpufreqd
(<http://cpufreqd.sourceforge.net/>) or a similar tool is installed and an
"cpu governor" (that's a kernel module) is loaded.

On Linux, if the system has the cpufreq-stats kernel module loaded, this
plugin reports the rate of p-state (cpu frequency) transitions and the per-
centage of time spent in each p-state.

On FreeBSD it does a sysctl dev.cpu.0.freq and submits this as instance 0.
At this time FreeBSD only has one frequency setting for all cores. See the
BUGS section in the FreeBSD man page for cpufreq(4) for more details.

On FreeBSD the plugin checks the success of sysctl dev.cpu.0.freq and un-
registers the plugin when this fails. A message will be logged to indicate
this.

Plugin "cpusleep"
This plugin doesn't have any options. It reads CLOCK_BOOTTIME and CLOCK_MO-
NOTONIC and reports the difference between these clocks. Since BOOTTIME
clock increments while device is suspended and MONOTONIC clock does not,
the derivative of the difference between these clocks gives the relative
amount of time the device has spent in suspend state. The recorded value is
in milliseconds of sleep per seconds of wall clock.

Plugin "csv"
DataDir Directory
Set the directory to store CSV-files under. Per default CSV-files are
generated beneath the daemon's working directory, i. e. the BaseDir.
The special strings stdout and stderr can be used to write to the stan-
dard output and standard error channels, respectively. This, of course,
only makes much sense when collectd is running in foreground- or
non-daemon-mode.

StoreRates true|false
If set to true, convert counter values to rates. If set to false (the
default) counter values are stored as is, i. e. as an increasing inte-
ger number.

cURL Statistics
All cURL-based plugins support collection of generic, request-based statis-
tics. These are disabled by default and can be enabled selectively for each
page or URL queried from the curl, curl_json, or curl_xml plugins. See the
documentation of those plugins for specific information. This section de-
scribes the available metrics that can be configured for each plugin. All
options are disabled by default.

See <http://curl.haxx.se/libcurl/c/curl_easy_getinfo.html> for more de-
tails.

TotalTime true|false
Total time of the transfer, including name resolving, TCP connect, etc.

NamelookupTime true|false
Time it took from the start until name resolving was completed.

ConnectTime true|false
Time it took from the start until the connect to the remote host (or
proxy) was completed.

AppconnectTime true|false
Time it took from the start until the SSL/SSH connect/handshake to the
remote host was completed.

PretransferTime true|false
Time it took from the start until just before the transfer begins.

StarttransferTime true|false
Time it took from the start until the first byte was received.

RedirectTime true|false
Time it took for all redirection steps include name lookup, connect,
pre-transfer and transfer before final transaction was started.

RedirectCount true|false
The total number of redirections that were actually followed.

SizeUpload true|false
The total amount of bytes that were uploaded.

SizeDownload true|false
The total amount of bytes that were downloaded.

SpeedDownload true|false
The average download speed that curl measured for the complete down-
load.

SpeedUpload true|false
The average upload speed that curl measured for the complete upload.

HeaderSize true|false
The total size of all the headers received.

RequestSize true|false
The total size of the issued requests.

ContentLengthDownload true|false
The content-length of the download.

ContentLengthUpload true|false
The specified size of the upload.

NumConnects true|false
The number of new connections that were created to achieve the trans-
fer.

Plugin "curl"
The curl plugin uses the libcurl (<http://curl.haxx.se/>) to read web pages
and the match infrastructure (the same code used by the tail plugin) to use
regular expressions with the received data.

The following example will read the current value of AMD stock from
Google's finance page and dispatch the value to collectd.

<Plugin curl>
<Page "stock_quotes">
Plugin "quotes"
URL "http://finance.google.com/finance?q=NYSE%3AAMD"
AddressFamily "any"
User "foo"
Password "bar"
Digest false
VerifyPeer true
VerifyHost true
CACert "/path/to/ca.crt"
Header "X-Custom-Header: foobar"
Post "foo=bar"

MeasureResponseTime false
MeasureResponseCode false

<Match>
Regex "<span +class=\"pr\"[^>]*> *([0-9]*\\.[0-9]+) *</span>"
DSType "GaugeAverage"
# Note: `stock_value' is not a standard type.
Type "stock_value"
Instance "AMD"
</Match>
</Page>
</Plugin>

In the Plugin block, there may be one or more Page blocks, each defining a
web page and one or more "matches" to be performed on the returned data.
The string argument to the Page block is used as plugin instance.

The following options are valid within Page blocks:

Plugin Plugin
Use Plugin as the plugin name when submitting values. Defaults to
"curl".

URL URL
URL of the web site to retrieve. Since a regular expression will be
used to extract information from this data, non-binary data is a big
plus here ;)

AddressFamily Type
IP version to resolve URL to. Useful in cases when hostname in URL re-
solves to both IPv4 and IPv6 addresses, and you are interested in using
one of them specifically. Use "ipv4" to enforce IPv4, "ipv6" to en-
force IPv6, or "any" to keep the default behavior of resolving ad-
dresses to all IP versions your system allows. If "libcurl" is com-
piled without IPv6 support, using "ipv6" will result in a warning and
fallback to "any". If "Type" cannot be parsed, a warning will be
printed and the whole Page block will be ignored.

User Name
Username to use if authorization is required to read the page.

Password Password
Password to use if authorization is required to read the page.

Digest true|false
Enable HTTP digest authentication.

VerifyPeer true|false
Enable or disable peer SSL certificate verification. See
<http://curl.haxx.se/docs/sslcerts.html> for details. Enabled by de-
fault.

CACert file
File that holds one or more SSL certificates. If you want to use HTTPS
you will possibly need this option. What CA certificates come bundled
with "libcurl" and are checked by default depends on the distribution
you use.

Header Header
A HTTP header to add to the request. Multiple headers are added if this
option is specified more than once.

Post Body
Specifies that the HTTP operation should be a POST instead of a GET.
The complete data to be posted is given as the argument. This option
will usually need to be accompanied by a Header option to set an appro-
priate "Content-Type" for the post body (e.g. to "applica-
tion/x-www-form-urlencoded").

MeasureResponseTime true|false
Measure response time for the request. If this setting is enabled,
Match blocks (see below) are optional. Disabled by default.

Beware that requests will get aborted if they take too long to com-
plete. Adjust Timeout accordingly if you expect MeasureResponseTime to
report such slow requests.

This option is similar to enabling the TotalTime statistic but it's
measured by collectd instead of cURL.

MeasureResponseCode true|false
Measure response code for the request. If this setting is enabled,
Match blocks (see below) are optional. Disabled by default.

<Statistics>
One Statistics block can be used to specify cURL statistics to be col-
lected for each request to the remote web site. See the section "cURL
Statistics" above for details. If this setting is enabled, Match blocks
(see below) are optional.

<Match>
One or more Match blocks that define how to match information in the
data returned by "libcurl". The "curl" plugin uses the same infrastruc-
ture that's used by the "tail" plugin, so please see the documentation
of the "tail" plugin below on how matches are defined. If the Measur-
eResponseTime or MeasureResponseCode options are set to true, Match
blocks are optional.

Interval Interval
Sets the interval (in seconds) in which the values will be collected
from this URL. By default the global Interval setting will be used.

Timeout Milliseconds
The Timeout option sets the overall timeout for HTTP requests to URL,
in milliseconds. By default, the configured Interval is used to set the
timeout. Prior to version 5.5.0, there was no timeout and requests
could hang indefinitely. This legacy behaviour can be achieved by set-
ting the value of Timeout to 0.

If Timeout is 0 or bigger than the Interval, keep in mind that each
slow network connection will stall one read thread. Adjust the
ReadThreads global setting accordingly to prevent this from blocking
other plugins.

Plugin "curl_json"
The curl_json plugin collects values from JSON data to be parsed by libyajl
(<https://lloyd.github.io/yajl/>) retrieved via either libcurl
(<http://curl.haxx.se/>) or read directly from a unix socket. The former
can be used, for example, to collect values from CouchDB documents (which
are stored JSON notation), and the latter to collect values from a uWSGI
stats socket.

The following example will collect several values from the built-in
"_stats" runtime statistics module of CouchDB
(<http://wiki.apache.org/couchdb/Runtime_Statistics>).

<Plugin curl_json>
<URL "http://localhost:5984/_stats">
AddressFamily "any"
Instance "httpd"
<Key "httpd/requests/count">
Type "http_requests"
</Key>

<Key "httpd_request_methods/*/count">
Type "http_request_methods"
</Key>

<Key "httpd_status_codes/*/count">
Type "http_response_codes"
</Key>
</URL>
</Plugin>

This example will collect data directly from a uWSGI "Stats Server" socket.

<Plugin curl_json>
<Sock "/var/run/uwsgi.stats.sock">
Instance "uwsgi"
<Key "workers/*/requests">
Type "http_requests"
</Key>

<Key "workers/*/apps/*/requests">
Type "http_requests"
</Key>
</Sock>
</Plugin>

In the Plugin block, there may be one or more URL blocks, each defining a
URL to be fetched via HTTP (using libcurl) or Sock blocks defining a unix
socket to read JSON from directly. Each of these blocks may have one or
more Key blocks.

The Key string argument must be in a path format. Each component is used to
match the key from a JSON map or the index of an JSON array. If a path com-
ponent of a Key is a * wildcard, the values for all map keys or array in-
dices will be collectd.

The following options are valid within URL blocks:

Host Name
Use Name as the host name when submitting values. Defaults to the
global host name setting.

Plugin Plugin
Use Plugin as the plugin name when submitting values. Defaults to
"curl_json".

Instance Instance
Sets the plugin instance to Instance.

Interval Interval
Sets the interval (in seconds) in which the values will be collected
from this URL. By default the global Interval setting will be used.

User Name
Password Password
Digest true|false
VerifyPeer true|false
VerifyHost true|false
CACert file
Header Header
Post Body
Timeout Milliseconds
These options behave exactly equivalent to the appropriate options of
the cURL plugin. Please see there for a detailed description.

<Statistics>
One Statistics block can be used to specify cURL statistics to be col-
lected for each request to the remote URL. See the section "cURL Sta-
tistics" above for details.

The following options are valid within Key blocks:

Type Type
Sets the type used to dispatch the values to the daemon. Detailed in-
formation about types and their configuration can be found in
types.db(5). This option is mandatory.

Instance Instance
Type-instance to use. Defaults to the current map key or current string
array element value.

Plugin "curl_jolokia"
The curl_jolokia plugin collects values from MBeanServevr - servlet engines
equipped with the jolokia (<https://jolokia.org>) MBean. It sends a
pre-configured JSON-Postbody to the servlet via HTTP commanding the jolokia
Bean to reply with a singe JSON equipped with all JMX counters requested.
By reducing TCP roundtrips in comparison to conventional JMX clients that
query one value via tcp at a time, it can return hundrets of values in one
roundtrip. Moreof - no java binding is required in collectd to do so.

It uses libyajl (<https://lloyd.github.io/yajl/>) to parse the Jolokia JSON
reply retrieved via libcurl (<http://curl.haxx.se/>)

<Plugin curl_jolokia>
<URL "http://10.10.10.10:7101/jolokia-war-1.2.0/?ignoreErrors=true&canonicalNaming=false";>
Host "_APPPERF_JMX"
User "webloginname"
Password "passvoid"
Post <JOLOKIA json post data>

<BeanName "PS_Scavenge">
MBean "java.lang:name=PS Scavenge,type=GarbageCollector"
BeanNameSpace "java_lang"
<AttributeName "collectiontime" >
Attribute "CollectionTime"
type "gauge"
</AttributeName>
<AttributeName "collectioncount" >
Attribute "CollectionCount"
type "gauge"
</AttributeName>
</BeanName>
</Plugin>

The plugin is intended to be written in a simple manner. Thus it doesn't
try to solve the task of generating the jolokia post data, or automatically
map the values, but rather leans on a verbose config containing the pre-
pared flat JSON post data and a config section per gauge transformed (as
one sample shown above). However, Jolokia can output all available gauges,
and we have a python script to filter them, and generate a configuration
for you:

jolokia_2_collectcfg.py

it can gather all interesting gauges, write a simple one value per line
config for itself and subsequent calls. You can remove lines from this
file manually, or create filter lists. You then use the script to generate
a collectd config. The script can then inspect data files from some
testruns, and remove all gauges, that don't contain any movement.

The base config looks like this:

The following options are valid within URL blocks:

Host Name
Use Name as the host name when submitting values. Defaults to the
global host name setting.

Plugin Plugin
Use Plugin as the plugin name when submitting values. Defaults to
"curl_jolokia".

Instance Instance
Sets the plugin instance to Instance.

Interval Interval
Sets the interval (in seconds) in which the values will be collected
from this URL. By default the global Interval setting will be used.

<BeanName>
One BeanName block configures the translation of the gauges of one bean
to their respective collectd names, where BeanName sets the main name.

MBean MBean
The name of the Bean on the server

BeanNameSpace BeanNameSpace
The name space the Bean resides under

AttributeName AttributeName
A bean can contain several Attributes with gauges. Each one can be
matched by a AttributeName section or be ignored.

Attribute Attribute
How should this attribute be called under the BeanName in the col-
lectd hierarchy?

Type Type
Sets the type used to dispatch the values to the daemon. Detailed
information about types and their configuration can be found in
types.db(5). This option is mandatory.

Plugin "curl_xml"
The curl_xml plugin uses libcurl (<http://curl.haxx.se/>) and libxml2
(<http://xmlsoft.org/>) to retrieve XML data via cURL.

<Plugin "curl_xml">
<URL "http://localhost/stats.xml">
AddressFamily "any"
Host "my_host"
#Plugin "curl_xml"
Instance "some_instance"
User "collectd"
Password "thaiNg0I"
VerifyPeer true
VerifyHost true
CACert "/path/to/ca.crt"
Header "X-Custom-Header: foobar"
Post "foo=bar"

<XPath "table[@id=\"magic_level\"]/tr">
Type "magic_level"
#InstancePrefix "prefix-"
InstanceFrom "td[1]"
#PluginInstanceFrom "td[1]"
ValuesFrom "td[2]/span[@class=\"level\"]"
</XPath>
</URL>
</Plugin>

In the Plugin block, there may be one or more URL blocks, each defining a
URL to be fetched using libcurl. Within each URL block there are options
which specify the connection parameters, for example authentication infor-
mation, and one or more XPath blocks.

Each XPath block specifies how to get one type of information. The string
argument must be a valid XPath expression which returns a list of "base el-
ements". One value is dispatched for each "base element". The type instance
and values are looked up using further XPath expressions that should be
relative to the base element.

Within the URL block the following options are accepted:

Host Name
Use Name as the host name when submitting values. Defaults to the
global host name setting.

Plugin Plugin
Use Plugin as the plugin name when submitting values. Defaults to
'curl_xml'.

Instance Instance
Use Instance as the plugin instance when submitting values. May be
overridden by PluginInstanceFrom option inside XPath blocks. Defaults
to an empty string (no plugin instance).

Interval Interval
Sets the interval (in seconds) in which the values will be collected
from this URL. By default the global Interval setting will be used.

Namespace Prefix URL
If an XPath expression references namespaces, they must be specified
with this option. Prefix is the "namespace prefix" used in the XML doc-
ument. URL is the "namespace name", an URI reference uniquely identi-
fying the namespace. The option can be repeated to register multiple
namespaces.

Examples:

Namespace "s" "http://schemas.xmlsoap.org/soap/envelope/"
Namespace "m" "http://www.w3.org/1998/Math/MathML"

User User
Password Password
Digest true|false
VerifyPeer true|false
VerifyHost true|false
CACert CA Cert File
Header Header
Post Body
Timeout Milliseconds
These options behave exactly equivalent to the appropriate options of
the cURL plugin. Please see there for a detailed description.

<Statistics>
One Statistics block can be used to specify cURL statistics to be col-
lected for each request to the remote URL. See the section "cURL Sta-
tistics" above for details.

<XPath XPath-expression>
Within each URL block, there must be one or more XPath blocks. Each
XPath block specifies how to get one type of information. The string
argument must be a valid XPath expression which returns a list of "base
elements". One value is dispatched for each "base element".

Within the XPath block the following options are accepted:

Type Type
Specifies the Type used for submitting patches. This determines the
number of values that are required / expected and whether the
strings are parsed as signed or unsigned integer or as double val-
ues. See types.db(5) for details. This option is required.

InstancePrefix InstancePrefix
Prefix the type instance with InstancePrefix. The values are simply
concatenated together without any separator. This option is op-
tional.

InstanceFrom InstanceFrom
Specifies a XPath expression to use for determining the type in-
stance. The XPath expression must return exactly one element. The
element's value is then used as type instance, possibly prefixed
with InstancePrefix (see above).

PluginInstanceFrom PluginInstanceFrom
Specifies a XPath expression to use for determining the plugin in-
stance. The XPath expression must return exactly one element. The
element's value is then used as plugin instance.

If the "base XPath expression" (the argument to the XPath block) re-
turns exactly one argument, then InstanceFrom and PluginInstanceFrom
may be omitted. Otherwise, at least one of InstanceFrom or PluginIn-
stanceFrom is required.

ValuesFrom ValuesFrom [ValuesFrom ...]
Specifies one or more XPath expression to use for reading the val-
ues. The number of XPath expressions must match the number of data
sources in the type specified with Type (see above). Each XPath ex-
pression must return exactly one element. The element's value is
then parsed as a number and used as value for the appropriate value
in the value list dispatched to the daemon. This option is re-
quired.

Plugin "dbi"
This plugin uses the dbi library (<http://libdbi.sourceforge.net/>) to con-
nect to various databases, execute SQL statements and read back the re-
sults. dbi is an acronym for "database interface" in case you were wonder-
ing about the name. You can configure how each column is to be interpreted
and the plugin will generate one or more data sets from each row returned
according to these rules.

Because the plugin is very generic, the configuration is a little more com-
plex than those of other plugins. It usually looks something like this:

<Plugin dbi>
<Query "out_of_stock">
Statement "SELECT category, COUNT(*) AS value FROM products WHERE in_stock = 0 GROUP BY category"
# Use with MySQL 5.0.0 or later
MinVersion 50000
<Result>
Type "gauge"
InstancePrefix "out_of_stock"
InstancesFrom "category"
ValuesFrom "value"
</Result>
</Query>
<Database "product_information">
#Plugin "warehouse"
Driver "mysql"
Interval 120
DriverOption "host" "localhost"
DriverOption "username" "collectd"
DriverOption "password" "aZo6daiw"
DriverOption "dbname" "prod_info"
SelectDB "prod_info"
Query "out_of_stock"
</Database>
</Plugin>

The configuration above defines one query with one result and one database.
The query is then linked to the database with the Query option within the
<Database> block. You can have any number of queries and databases and you
can also use the Include statement to split up the configuration file in
multiple, smaller files. However, the <Query> block must precede the <Data-
base> blocks, because the file is interpreted from top to bottom!

The following is a complete list of options:

Query blocks

Query blocks define SQL statements and how the returned data should be in-
terpreted. They are identified by the name that is given in the opening
line of the block. Thus the name needs to be unique. Other than that, the
name is not used in collectd.

In each Query block, there is one or more Result blocks. Result blocks de-
fine which column holds which value or instance information. You can use
multiple Result blocks to create multiple values from one returned row.
This is especially useful, when queries take a long time and sending almost
the same query again and again is not desirable.

Example:

<Query "environment">
Statement "select station, temperature, humidity from environment"
<Result>
Type "temperature"
# InstancePrefix "foo"
InstancesFrom "station"
ValuesFrom "temperature"
</Result>
<Result>
Type "humidity"
InstancesFrom "station"
ValuesFrom "humidity"
</Result>
</Query>

The following options are accepted:

Statement SQL
Sets the statement that should be executed on the server. This is not
interpreted by collectd, but simply passed to the database server.
Therefore, the SQL dialect that's used depends on the server collectd
is connected to.

The query has to return at least two columns, one for the instance and
one value. You cannot omit the instance, even if the statement is guar-
anteed to always return exactly one line. In that case, you can usually
specify something like this:

Statement "SELECT \"instance\", COUNT(*) AS value FROM table"

(That works with MySQL but may not be valid SQL according to the spec.
If you use a more strict database server, you may have to select from a
dummy table or something.)

Please note that some databases, for example Oracle, will fail if you
include a semicolon at the end of the statement.

MinVersion Version
MaxVersion Value
Only use this query for the specified database version. You can use
these options to provide multiple queries with the same name but with a
slightly different syntax. The plugin will use only those queries,
where the specified minimum and maximum versions fit the version of the
database in use.

The database version is determined by "dbi_conn_get_engine_version",
see the libdbi documentation <http://libdbi.sourceforge.net/docs/pro-
grammers-guide/reference-conn.html#DBI-CONN-GET-ENGINE-VERSION> for de-
tails. Basically, each part of the version is assumed to be in the
range from 00 to 99 and all dots are removed. So version "4.1.2" be-
comes "40102", version "5.0.42" becomes "50042".

Warning: The plugin will use all matching queries, so if you specify
multiple queries with the same name and overlapping ranges, weird stuff
will happen. Don't to it! A valid example would be something along
these lines:

MinVersion 40000
MaxVersion 49999
...
MinVersion 50000
MaxVersion 50099
...
MinVersion 50100
# No maximum

In the above example, there are three ranges that don't overlap. The
last one goes from version "5.1.0" to infinity, meaning "all later ver-
sions". Versions before "4.0.0" are not specified.

Type Type
The type that's used for each line returned. See types.db(5) for more
details on how types are defined. In short: A type is a predefined lay-
out of data and the number of values and type of values has to match
the type definition.

If you specify "temperature" here, you need exactly one gauge column.
If you specify "if_octets", you will need two counter columns. See the
ValuesFrom setting below.

There must be exactly one Type option inside each Result block.

InstancePrefix prefix
Prepends prefix to the type instance. If InstancesFrom (see below) is
not given, the string is simply copied. If InstancesFrom is given, pre-
fix and all strings returned in the appropriate columns are concate-
nated together, separated by dashes ("-").

InstancesFrom column0 [column1 ...]
Specifies the columns whose values will be used to create the "type-in-
stance" for each row. If you specify more than one column, the value of
all columns will be joined together with dashes ("-") as separation
characters.

The plugin itself does not check whether or not all built instances are
different. It's your responsibility to assure that each is unique. This
is especially true, if you do not specify InstancesFrom: You have to
make sure that only one row is returned in this case.

If neither InstancePrefix nor InstancesFrom is given, the type-instance
will be empty.

ValuesFrom column0 [column1 ...]
Names the columns whose content is used as the actual data for the data
sets that are dispatched to the daemon. How many such columns you need
is determined by the Type setting above. If you specify too many or not
enough columns, the plugin will complain about that and no data will be
submitted to the daemon.

The actual data type in the columns is not that important. The plugin
will automatically cast the values to the right type if it know how to
do that. So it should be able to handle integer an floating point
types, as well as strings (if they include a number at the beginning).

There must be at least one ValuesFrom option inside each Result block.

MetadataFrom [column0 column1 ...]
Names the columns whose content is used as metadata for the data sets
that are dispatched to the daemon.

Database blocks

Database blocks define a connection to a database and which queries should
be sent to that database. Since the used "dbi" library can handle a wide
variety of databases, the configuration is very generic. If in doubt, refer
to libdbi's documentation - we stick as close to the terminology used
there.

Each database needs a "name" as string argument in the starting tag of the
block. This name will be used as "PluginInstance" in the values submitted
to the daemon. Other than that, that name is not used.

Plugin Plugin
Use Plugin as the plugin name when submitting query results from this
Database. Defaults to "dbi".

Interval Interval
Sets the interval (in seconds) in which the values will be collected
from this database. By default the global Interval setting will be
used.

Driver Driver
Specifies the driver to use to connect to the database. In many cases
those drivers are named after the database they can connect to, but
this is not a technical necessity. These drivers are sometimes referred
to as "DBD", DataBase Driver, and some distributions ship them in sepa-
rate packages. Drivers for the "dbi" library are developed by the lib-
dbi-drivers project at <http://libdbi-drivers.sourceforge.net/>.

You need to give the driver name as expected by the "dbi" library here.
You should be able to find that in the documentation for each driver.
If you mistype the driver name, the plugin will dump a list of all
known driver names to the log.

DriverOption Key Value
Sets driver-specific options. What option a driver supports can be
found in the documentation for each driver, somewhere at <http://lib-
dbi-drivers.sourceforge.net/>. However, the options "host", "username",
"password", and "dbname" seem to be de facto standards.

DBDs can register two types of options: String options and numeric op-
tions. The plugin will use the "dbi_conn_set_option" function when the
configuration provides a string and the "dbi_conn_require_option_nu-
meric" function when the configuration provides a number. So these two
lines will actually result in different calls being used:

DriverOption "Port" 1234 # numeric
DriverOption "Port" "1234" # string

Unfortunately, drivers are not too keen to report errors when an un-
known option is passed to them, so invalid settings here may go unno-
ticed. This is not the plugin's fault, it will report errors if it gets
them from the library / the driver. If a driver complains about an op-
tion, the plugin will dump a complete list of all options understood by
that driver to the log. There is no way to programmatically find out if
an option expects a string or a numeric argument, so you will have to
refer to the appropriate DBD's documentation to find this out. Sorry.

SelectDB Database
In some cases, the database name you connect with is not the database
name you want to use for querying data. If this option is set, the plu-
gin will "select" (switch to) that database after the connection is es-
tablished.

Query QueryName
Associates the query named QueryName with this database connection. The
query needs to be defined before this statement, i. e. all query blocks
you want to refer to must be placed above the database block you want
to refer to them from.

Host Hostname
Sets the host field of value lists to Hostname when dispatching values.
Defaults to the global hostname setting.

Plugin "dcpmm"
The dcpmm plugin will collect Intel(R) Optane(TM) DC Persistent Memory re-
lated performance statistics. The plugin requires root privileges to per-
form the statistics collection.

Synopsis:

<Plugin "dcpmm">
Interval 10.0
CollectHealth false
CollectPerfMetrics true
EnableDispatchAll false
</Plugin>

Interval time in seconds
Sets the Interval (in seconds) in which the values will be collected.
Defaults to "global Interval" value. This will override the global In-
terval for dcpmm plugin. None of the other plugins will be affected.

CollectHealth true|false
Collects health information. CollectHealth and CollectPerfMetrics can-
not be true at the same time. Defaults to "false".

The health information metrics are the following:
health_status Overall health summary (0: normal | 1:
non-critical | 2: critical | 3: fatal).
lifespan_remaining The moduleas remaining life as a percent-
age value of factory expected life span.
lifespan_used The moduleas used life as a percentage
value of factory expected life span.
power_on_time The lifetime the DIMM has been powered on
in seconds.
uptime The current uptime of the DIMM for the
current power cycle in seconds.
last_shutdown_time The time the system was last shutdown. The
time is represented in epoch (seconds).
media_temperature The mediaas current temperature in degree
Celsius.
controller_temperature The controlleras current temperature in
degree Celsius.
max_media_temperature The mediaas the highest temperature re-
ported in degree Celsius.
max_controller_temperature The controlleras highest temperature re-
ported in degree Celsius.
tsc_cycles The number of tsc cycles during each in-
terval.
epoch The timestamp in seconds at which the met-
rics are collected from DCPMM DIMMs.

CollectPerfMetrics true|false
Collects memory performance metrics. CollectHealth and CollectPerfMet-
rics cannot be true at the same time. Defaults to "true".

The memory performance metrics are the following:
total_bytes_read Number of bytes transacted by the read opera-
tions.
total_bytes_written Number of bytes transacted by the write opera-
tions.
read_64B_ops_rcvd Number of read operations performed to the physi-
cal media in 64 bytes granularity.
write_64B_ops_rcvd Number of write operations performed to the phys-
ical media in 64 bytes granularity.
media_read_ops Number of read operations performed to the physi-
cal media.
media_write_ops Number of write operations performed to the phys-
ical media.
host_reads Number of read operations received from the CPU
(memory controller).
host_writes Number of write operations received from the CPU
(memory controller).
read_hit_ratio Measures the efficiency of the buffer in the read
path. Range of 0.0 - 1.0.
write_hit_ratio Measures the efficiency of the buffer in the
write path. Range of 0.0 - 1.0.
tsc_cycles The number of tsc cycles during each interval.
epoch The timestamp in seconds at which the metrics are
collected from DCPMM DIMMs.

EnableDispatchAll false
This parameter helps to seamlessly enable simultaneous health and mem-
ory perf metrics collection in future. This is unused at the moment
and must always be false.

Plugin "df"
Device Device
Select partitions based on the devicename.

See /"IGNORELISTS" for details.

MountPoint Directory
Select partitions based on the mountpoint.

See /"IGNORELISTS" for details.

FSType FSType
Select partitions based on the filesystem type.

See /"IGNORELISTS" for details.

IgnoreSelected true|false
Invert the selection: If set to true, all partitions except the ones
that match any one of the criteria are collected. By default only se-
lected partitions are collected if a selection is made. If no selection
is configured at all, all partitions are selected.

LogOnce false|false
Only log stat() errors once.

ReportByDevice true|false
Report using the device name rather than the mountpoint. i.e. with this
false, (the default), it will report a disk as "root", but with it
true, it will be "sda1" (or whichever).

ReportInodes true|false
Enables or disables reporting of free, reserved and used inodes. De-
faults to inode collection being disabled.

Enable this option if inodes are a scarce resource for you, usually be-
cause many small files are stored on the disk. This is a usual scenario
for mail transfer agents and web caches.

ValuesAbsolute true|false
Enables or disables reporting of free and used disk space in 1K-blocks.
Defaults to true.

ValuesPercentage false|true
Enables or disables reporting of free and used disk space in percent-
age. Defaults to false.

This is useful for deploying collectd on the cloud, where machines with
different disk size may exist. Then it is more practical to configure
thresholds based on relative disk size.

Plugin "disk"
The "disk" plugin collects information about the usage of physical disks
and logical disks (partitions). Values collected are the number of octets
written to and read from a disk or partition, the number of read/write op-
erations issued to the disk and a rather complex "time" it took for these
commands to be issued.

Using the following two options you can ignore some disks or configure the
collection only of specific disks.

Disk Name
Select the disk Name. Whether it is collected or ignored depends on the
IgnoreSelected setting, see below. As with other plugins that use the
daemon's ignorelist functionality, a string that starts and ends with a
slash is interpreted as a regular expression. Examples:

Disk "sdd"
Disk "/hda[34]/"

See /"IGNORELISTS" for details.

IgnoreSelected true|false
Sets whether selected disks, i. e. the ones matches by any of the Disk
statements, are ignored or if all other disks are ignored. The behavior
(hopefully) is intuitive: If no Disk option is configured, all disks
are collected. If at least one Disk option is given and no IgnoreSe-
lected or set to false, only matching disks will be collected. If Ig-
noreSelected is set to true, all disks are collected except the ones
matched.

UseBSDName true|false
Whether to use the device's "BSD Name", on Mac OS X, instead of the de-
fault major/minor numbers. Requires collectd to be built with Apple's
IOKitLib support.

UdevNameAttr Attribute
Attempt to override disk instance name with the value of a specified
udev attribute when built with libudev. If the attribute is not de-
fined for the given device, the default name is used. Example:

UdevNameAttr "DM_NAME"

Please note that using an attribute that does not differentiate between
the whole disk and its particular partitions (like ID_SERIAL) will re-
sult in data about the whole disk and each partition being mixed to-
gether incorrectly. In this case, you can use ID_COLLECTD attribute
that is provided by contrib/99-storage-collectd.rules udev rule file
instead.

Plugin "dns"
Interface Interface
The dns plugin uses libpcap to capture dns traffic and analyzes it.
This option sets the interface that should be used. If this option is
not set, or set to "any", the plugin will try to get packets from all
interfaces. This may not work on certain platforms, such as Mac OS X.

IgnoreSource IP-address
Ignore packets that originate from this address.

SelectNumericQueryTypes true|false
Enabled by default, collects unknown (and thus presented as numeric
only) query types.

Plugin "dpdkevents"
The dpdkevents plugin collects events from DPDK such as link status of net-
work ports and Keep Alive status of DPDK logical cores. In order to get
Keep Alive events following requirements must be met: - DPDK >= 16.07 -
support for Keep Alive implemented in DPDK application. More details can be
found here: http://dpdk.org/doc/guides/sample_app_ug/keep_alive.html

Synopsis:

<Plugin "dpdkevents">
<EAL>
Coremask "0x1"
MemoryChannels "4"
FilePrefix "rte"
</EAL>
<Event "link_status">
SendEventsOnUpdate true
EnabledPortMask 0xffff
PortName "interface1"
PortName "interface2"
SendNotification false
</Event>
<Event "keep_alive">
SendEventsOnUpdate true
LCoreMask "0xf"
KeepAliveShmName "/dpdk_keepalive_shm_name"
SendNotification false
</Event>
</Plugin>

Options:

The EAL block

Coremask Mask
Memorychannels Channels
Number of memory channels per processor socket.

FilePrefix File
The prefix text used for hugepage filenames. The filename will be set
to /var/run/.<prefix>_config where prefix is what is passed in by the
user.

The Event block

The Event block defines configuration for specific event. It accepts a sin-
gle argument which specifies the name of the event.

Link Status event

SendEventOnUpdate true|false
If set to true link status value will be dispatched only when it is
different from previously read value. This is an optional argument -
default value is true.

EnabledPortMask Mask
A hexidecimal bit mask of the DPDK ports which should be enabled. A
mask of 0x0 means that all ports will be disabled. A bitmask of all F's
means that all ports will be enabled. This is an optional argument - by
default all ports are enabled.

PortName Name
A string containing an optional name for the enabled DPDK ports. Each
PortName option should contain only one port name; specify as many
PortName options as desired. Default naming convention will be used if
PortName is blank. If there are less PortName options than there are
enabled ports, the default naming convention will be used for the addi-
tional ports.

SendNotification true|false
If set to true, link status notifications are sent, instead of link
status being collected as a statistic. This is an optional argument -
default value is false.

Keep Alive event

SendEventOnUpdate true|false
If set to true keep alive value will be dispatched only when it is dif-
ferent from previously read value. This is an optional argument - de-
fault value is true.

LCoreMask Mask
An hexadecimal bit mask of the logical cores to monitor keep alive
state.

KeepAliveShmName Name
Shared memory name identifier that is used by secondary process to mon-
itor the keep alive cores state.

SendNotification true|false
If set to true, keep alive notifications are sent, instead of keep
alive information being collected as a statistic. This is an optional
argument - default value is false.

Plugin "dpdkstat"
The dpdkstat plugin collects information about DPDK interfaces using the
extended NIC stats API in DPDK.

Synopsis:

<Plugin "dpdkstat">
<EAL>
Coremask "0x4"
MemoryChannels "4"
FilePrefix "rte"
SocketMemory "1024"
LogLevel "7"
RteDriverLibPath "/usr/lib/dpdk-pmd"
</EAL>
SharedMemObj "dpdk_collectd_stats_0"
EnabledPortMask 0xffff
PortName "interface1"
PortName "interface2"
</Plugin>

Options:

The EAL block

Coremask Mask
A string containing an hexadecimal bit mask of the cores to run on.
Note that core numbering can change between platforms and should be de-
termined beforehand.

Memorychannels Channels
A string containing a number of memory channels per processor socket.

FilePrefix File
The prefix text used for hugepage filenames. The filename will be set
to /var/run/.<prefix>_config where prefix is what is passed in by the
user.

SocketMemory MB
A string containing amount of Memory to allocate from hugepages on spe-
cific sockets in MB. This is an optional value.

LogLevel LogLevel_number
A string containing log level number. This parameter is optional. If
parameter is not present then default value "7" - (INFO) is used.
Value "8" - (DEBUG) can be set to enable debug traces.

RteDriverLibPath Path
A string containing path to shared pmd driver lib or path to directory,
where shared pmd driver libs are available. This parameter is optional.
This parameter enable loading of shared pmd driver libs from defined
path. E.g.: "/usr/lib/dpdk-pmd/librte_pmd_i40e.so" or
"/usr/lib/dpdk-pmd"

SharedMemObj Mask
A string containing the name of the shared memory object that should be
used to share stats from the DPDK secondary process to the collectd dpd-
kstat plugin. Defaults to dpdk_collectd_stats if no other value is con-
figured.

EnabledPortMask Mask
A hexidecimal bit mask of the DPDK ports which should be enabled. A mask
of 0x0 means that all ports will be disabled. A bitmask of all Fs means
that all ports will be enabled. This is an optional argument - default
is all ports enabled.

PortName Name
A string containing an optional name for the enabled DPDK ports. Each
PortName option should contain only one port name; specify as many Port-
Name options as desired. Default naming convention will be used if Port-
Name is blank. If there are less PortName options than there are enabled
ports, the default naming convention will be used for the additional
ports.

Plugin "dpdk_telemetry"
The dpdk_telemetry plugin collects DPDK ethernet device metrics via
dpdk_telemetry library.

The plugin retrieves metrics from a DPDK packet forwarding application by
sending the JSON formatted message via a UNIX domain socket. The DPDK
telemetry component will respond with a JSON formatted reply, delivering
the requested metrics. The plugin parses the JSON data, and publishes the
metric values to collectd for further use.

Synopsis:

<Plugin dpdk_telemetry>
ClientSocketPath "/var/run/.client"
DpdkSocketPath "/var/run/dpdk/rte/telemetry"
</Plugin>

Options:

ClientSocketPath Client_Path
The UNIX domain client socket at Client_Path to receive messages from
DPDK telemetry library. Defaults to "/var/run/.client".

DpdkSocketPath Dpdk_Path
The UNIX domain DPDK telemetry socket to be connected at Dpdk_Path to
send messages. Defaults to "/var/run/dpdk/rte/telemetry".

Plugin "email"
SocketFile Path
Sets the socket-file which is to be created.

SocketGroup Group
If running as root change the group of the UNIX-socket after it has
been created. Defaults to collectd.

SocketPerms Permissions
Change the file permissions of the UNIX-socket after it has been cre-
ated. The permissions must be given as a numeric, octal value as you
would pass to chmod(1). Defaults to 0770.

MaxConns Number
Sets the maximum number of connections that can be handled in parallel.
Since this many threads will be started immediately setting this to a
very high value will waste valuable resources. Defaults to 5 and will
be forced to be at most 16384 to prevent typos and dumb mistakes.

Plugin "ethstat"
The ethstat plugin collects information about network interface cards
(NICs) by talking directly with the underlying kernel driver using
ioctl(2).

Synopsis:

<Plugin "ethstat">
Interface "eth0"
Map "rx_csum_offload_errors" "if_rx_errors" "checksum_offload"
Map "multicast" "if_multicast"
</Plugin>

Options:

Interface Name
Collect statistical information about interface Name.

Map Name Type [TypeInstance]
By default, the plugin will submit values as type "derive" and type in-
stance set to Name, the name of the metric as reported by the driver.
If an appropriate Map option exists, the given Type and, optionally,
TypeInstance will be used.

MappedOnly true|false
When set to true, only metrics that can be mapped to a type will be
collected, all other metrics will be ignored. Defaults to false.

Plugin "exec"
Please make sure to read collectd-exec(5) before using this plugin. It con-
tains valuable information on when the executable is executed and the out-
put that is expected from it.

Exec User[:[Group]] Executable [<arg> [<arg> ...]]
NotificationExec User[:[Group]] Executable [<arg> [<arg> ...]]
Execute the executable Executable as user User. If the user name is
followed by a colon and a group name, the effective group is set to
that group. The real group and saved-set group will be set to the de-
fault group of that user. If no group is given the effective group ID
will be the same as the real group ID.

Please note that in order to change the user and/or group the daemon
needs superuser privileges. If the daemon is run as an unprivileged
user you must specify the same user/group here. If the daemon is run
with superuser privileges, you must supply a non-root user here.

The executable may be followed by optional arguments that are passed to
the program. Please note that due to the configuration parsing numbers
and boolean values may be changed. If you want to be absolutely sure
that something is passed as-is please enclose it in quotes.

The Exec and NotificationExec statements change the semantics of the
programs executed, i. e. the data passed to them and the response ex-
pected from them. This is documented in great detail in col-
lectd-exec(5).

Plugin "fhcount"
The "fhcount" plugin provides statistics about used, unused and total num-
ber of file handles on Linux.

The fhcount plugin provides the following configuration options:

ValuesAbsolute true|false
Enables or disables reporting of file handles usage in absolute num-
bers, e.g. file handles used. Defaults to true.

ValuesPercentage false|true
Enables or disables reporting of file handles usage in percentages,
e.g. percent of file handles used. Defaults to false.

Plugin "filecount"
The "filecount" plugin counts the number of files in a certain directory
(and its subdirectories) and their combined size. The configuration is very
straight forward:

<Plugin "filecount">
<Directory "/var/qmail/queue/mess">
Instance "qmail-message"
</Directory>
<Directory "/var/qmail/queue/todo">
Instance "qmail-todo"
</Directory>
<Directory "/var/db/php5">
Instance "php5-sessions"
Name "sess_*"
</Directory>
</Plugin>

The example above counts the number of files in QMail's queue directories
and the number of PHP5 sessions. Jfiy: The "todo" queue holds the messages
that QMail has not yet looked at, the "message" queue holds the messages
that were classified into "local" and "remote".

As you can see, the configuration consists of one or more "Directory"
blocks, each of which specifies a directory in which to count the files.
Within those blocks, the following options are recognized:

Plugin Plugin
Use Plugin as the plugin name when submitting values. Defaults to
filecount.

Instance Instance
Sets the plugin instance to Instance. If not given, the instance is set
to the directory name with all slashes replaced by underscores and all
leading underscores removed. Empty value is allowed.

Name Pattern
Only count files that match Pattern, where Pattern is a shell-like
wildcard as understood by fnmatch(3). Only the filename is checked
against the pattern, not the entire path. In case this makes it easier
for you: This option has been named after the -name parameter to
find(1).

MTime Age
Count only files of a specific age: If Age is greater than zero, only
files that haven't been touched in the last Age seconds are counted. If
Age is a negative number, this is inversed. For example, if -60 is
specified, only files that have been modified in the last minute will
be counted.

The number can also be followed by a "multiplier" to easily specify a
larger timespan. When given in this notation, the argument must in
quoted, i. e. must be passed as string. So the -60 could also be writ-
ten as "-1m" (one minute). Valid multipliers are "s" (second), "m"
(minute), "h" (hour), "d" (day), "w" (week), and "y" (year). There is
no "month" multiplier. You can also specify fractional numbers, e. g.
"0.5d" is identical to "12h".

Size Size
Count only files of a specific size. When Size is a positive number,
only files that are at least this big are counted. If Size is a nega-
tive number, this is inversed, i. e. only files smaller than the ab-
solute value of Size are counted.

As with the MTime option, a "multiplier" may be added. For a detailed
description see above. Valid multipliers here are "b" (byte), "k"
(kilobyte), "m" (megabyte), "g" (gigabyte), "t" (terabyte), and "p"
(petabyte). Please note that there are 1000 bytes in a kilobyte, not
1024.

Recursive true|false
Controls whether or not to recurse into subdirectories. Enabled by de-
fault.

IncludeHidden true|false
Controls whether or not to include "hidden" files and directories in
the count. "Hidden" files and directories are those, whose name begins
with a dot. Defaults to false, i.e. by default hidden files and direc-
tories are ignored.

RegularOnly true|false
Controls whether or not to include only regular files in the count.
Defaults to true, i.e. by default non regular files are ignored.

FilesSizeType Type
Sets the type used to dispatch files combined size. Empty value ("")
disables reporting. Defaults to bytes.

FilesCountType Type
Sets the type used to dispatch number of files. Empty value ("") dis-
ables reporting. Defaults to files.

TypeInstance Instance
Sets the type instance used to dispatch values. Defaults to an empty
string (no plugin instance).

Plugin "GenericJMX"
The GenericJMX plugin is written in Java and therefore documented in col-
lectd-java(5).

Plugin "gmond"
The gmond plugin received the multicast traffic sent by gmond, the statis-
tics collection daemon of Ganglia. Mappings for the standard "metrics" are
built-in, custom mappings may be added via Metric blocks, see below.

Synopsis:

<Plugin "gmond">
MCReceiveFrom "239.2.11.71" "8649"
<Metric "swap_total">
Type "swap"
TypeInstance "total"
DataSource "value"
</Metric>
<Metric "swap_free">
Type "swap"
TypeInstance "free"
DataSource "value"
</Metric>
</Plugin>

The following metrics are built-in:

* load_one, load_five, load_fifteen

* cpu_user, cpu_system, cpu_idle, cpu_nice, cpu_wio

* mem_free, mem_shared, mem_buffers, mem_cached, mem_total

* bytes_in, bytes_out

* pkts_in, pkts_out

Available configuration options:

MCReceiveFrom MCGroup [Port]
Sets sets the multicast group and UDP port to which to subscribe.

Default: 239.2.11.71 / 8649

<Metric Name>
These blocks add a new metric conversion to the internal table. Name,
the string argument to the Metric block, is the metric name as used by
Ganglia.

Type Type
Type to map this metric to. Required.

TypeInstance Instance
Type-instance to use. Optional.

DataSource Name
Data source to map this metric to. If the configured type has ex-
actly one data source, this is optional. Otherwise the option is
required.

Plugin "gps"
The "gps plugin" connects to gpsd on the host machine. The host, port,
timeout and pause are configurable.

This is useful if you run an NTP server using a GPS for source and you want
to monitor it.

Mind your GPS must send $--GSA for having the data reported!

The following elements are collected:

satellites
Number of satellites used for fix (type instance "used") and in view
(type instance "visible"). 0 means no GPS satellites are visible.

dilution_of_precision
Vertical and horizontal dilution (type instance "horizontal" or "verti-
cal"). It should be between 0 and 3. Look at the documentation of
your GPS to know more.

Synopsis:

LoadPlugin gps
<Plugin "gps">
# Connect to localhost on gpsd regular port:
Host "127.0.0.1"
Port "2947"
# 15 ms timeout
Timeout 0.015
# PauseConnect of 5 sec. between connection attempts.
PauseConnect 5
</Plugin>

Available configuration options:

Host Host
The host on which gpsd daemon runs. Defaults to localhost.

Port Port
Port to connect to gpsd on the host machine. Defaults to 2947.

Timeout Seconds
Timeout in seconds (default 0.015 sec).

The GPS data stream is fetch by the plugin form the daemon. It waits
for data to be available, if none arrives it times out and loop for an-
other reading. Mind to put a low value gpsd expects value in the mi-
cro-seconds area (recommended is 500 us) since the waiting function is
blocking. Value must be between 500 us and 5 sec., if outside that
range the default value is applied.

This only applies from gpsd release-2.95.

PauseConnect Seconds
Pause to apply between attempts of connection to gpsd in seconds (de-
fault 5 sec).

Plugin "gpu_nvidia"
Efficiently collects various statistics from the system's NVIDIA GPUs using
the NVML library. Currently collected are fan speed, core temperature, per-
cent load, percent memory used, compute and memory frequencies, and power
consumption.

GPUIndex
If one or more of these options is specified, only GPUs at that index
(as determined by nvidia-utils through nvidia-smi) have statistics col-
lected. If no instance of this option is specified, all GPUs are moni-
tored.

IgnoreSelected
If set to true, all detected GPUs except the ones at indices specified
by GPUIndex entries are collected. For greater clarity, setting Ignore-
Selected without any GPUIndex directives will result in no statistics
being collected.

InstanceByGPUIndex
If set to false, the GPU ID will not be part of the plugin instance.
The default is 'GPU ID'-'GPU name'

InstanceByGPUName
If set to false, the GPU name will not be part of the plugin instance.
The default is 'GPU ID'-'GPU name'

Plugin "grpc"
The grpc plugin provides an RPC interface to submit values to or query val-
ues from collectd based on the open source gRPC framework. It exposes an
end-point for dispatching values to the daemon.

The gRPC homepage can be found at <https://grpc.io/>.

Server Host Port
The Server statement sets the address of a server to which to send met-
rics via the "DispatchValues" function.

The argument Host may be a hostname, an IPv4 address, or an IPv6 ad-
dress.

Optionally, Server may be specified as a configuration block which sup-
ports the following options:

EnableSSL false|true
Whether to require SSL for outgoing connections. Default: false.

SSLCACertificateFile Filename
SSLCertificateFile Filename
SSLCertificateKeyFile Filename
Filenames specifying SSL certificate and key material to be used
with SSL connections.

Listen Host Port
The Listen statement sets the network address to bind to. When multiple
statements are specified, the daemon will bind to all of them. If none
are specified, it defaults to 0.0.0.0:50051.

The argument Host may be a hostname, an IPv4 address, or an IPv6 ad-
dress.

Optionally, Listen may be specified as a configuration block which sup-
ports the following options:

EnableSSL true|false
Whether to enable SSL for incoming connections. Default: false.

SSLCACertificateFile Filename
SSLCertificateFile Filename
SSLCertificateKeyFile Filename
Filenames specifying SSL certificate and key material to be used
with SSL connections.

VerifyPeer true|false
When enabled, a valid client certificate is required to connect to
the server. When disabled, a client certifiacte is not requested
and any unsolicited client certificate is accepted. Enabled by de-
fault.

Plugin "hddtemp"
To get values from hddtemp collectd connects to localhost (127.0.0.1), port
7634/tcp. The Host and Port options can be used to change these default
values, see below. "hddtemp" has to be running to work correctly. If "hd-
dtemp" is not running timeouts may appear which may interfere with other
statistics..

The hddtemp homepage can be found at <http://www.guzu.net/linux/hd-
dtemp.php>.

Host Hostname
Hostname to connect to. Defaults to 127.0.0.1.

Port Port
TCP-Port to connect to. Defaults to 7634.

Plugin "hugepages"
To collect hugepages information, collectd reads directories "/sys/de-
vices/system/node/*/hugepages" and "/sys/kernel/mm/hugepages". Reading of
these directories can be disabled by the following options (default is en-
abled).

ReportPerNodeHP true|false
If enabled, information will be collected from the hugepage counters in
"/sys/devices/system/node/*/hugepages". This is used to check the
per-node hugepage statistics on a NUMA system.

ReportRootHP true|false
If enabled, information will be collected from the hugepage counters in
"/sys/kernel/mm/hugepages". This can be used on both NUMA and non-NUMA
systems to check the overall hugepage statistics.

ValuesPages true|false
Whether to report hugepages metrics in number of pages. Defaults to
true.

ValuesBytes false|true
Whether to report hugepages metrics in bytes. Defaults to false.

ValuesPercentage false|true
Whether to report hugepages metrics as percentage. Defaults to false.

Plugin "infiniband"
The "infiniband" plugin collects information about IB ports. Metrics are
gathered from "/sys/class/infiniband/DEVICE/port/PORTNUM/*", and Port names
are formatted like "DEVICE:PORTNUM" (see examples below).

Options:

Port Port
Select the port Port. Whether it is collected or ignored depends on the
IgnoreSelected setting, see below. As with other plugins that use the
daemon's ignorelist functionality, a string that starts and ends with a
slash is interpreted as a regular expression. Examples:

Port "mlx5_0:1"
Port "/mthca0:[0-9]/"

See /"IGNORELISTS" for details.

IgnoreSelected true|false
Sets whether selected ports are ignored or if all other ports are ig-
nored. The behavior (hopefully) is intuitive: If no Port option is con-
figured, all ports are collected. If at least one Port option is given
and IgnoreSelected is not given or set to false, only matching ports
will be collected. If IgnoreSelected is set to true, all ports are col-
lected except the ones matched.

Plugin "intel_pmu"
The intel_pmu plugin collects performance counters data on Intel CPUs using
Linux perf interface. All events are reported on a per core basis.

Synopsis:

<Plugin intel_pmu>
ReportHardwareCacheEvents true
ReportKernelPMUEvents true
ReportSoftwareEvents true
EventList "/var/cache/pmu/GenuineIntel-6-2D-core.json"
HardwareEvents "L2_RQSTS.CODE_RD_HIT,L2_RQSTS.CODE_RD_MISS" "L2_RQSTS.ALL_CODE_RD"
Cores "0-3" "4,6" "[12-15]"
DispatchMultiPmu false
</Plugin>

Options:

ReportHardwareCacheEvents false|true
Enable or disable measuring of hardware CPU cache events:
- L1-dcache-loads
- L1-dcache-load-misses
- L1-dcache-stores
- L1-dcache-store-misses
- L1-dcache-prefetches
- L1-dcache-prefetch-misses
- L1-icache-loads
- L1-icache-load-misses
- L1-icache-prefetches
- L1-icache-prefetch-misses
- LLC-loads
- LLC-load-misses
- LLC-stores
- LLC-store-misses
- LLC-prefetches
- LLC-prefetch-misses
- dTLB-loads
- dTLB-load-misses
- dTLB-stores
- dTLB-store-misses
- dTLB-prefetches
- dTLB-prefetch-misses
- iTLB-loads
- iTLB-load-misses
- branch-loads
- branch-load-misses

ReportKernelPMUEvents false|true
Enable or disable measuring of the following events:
- cpu-cycles
- instructions
- cache-references
- cache-misses
- branches
- branch-misses
- bus-cycles

ReportSoftwareEvents false|true
Enable or disable measuring of software events provided by kernel:
- cpu-clock
- task-clock
- context-switches
- cpu-migrations
- page-faults
- minor-faults
- major-faults
- alignment-faults
- emulation-faults

EventList filename
JSON performance counter event list file name. To be able to monitor
all Intel CPU specific events JSON event list file should be down-
loaded. Use the pmu-tools event_download.py script to download event
list for current CPU.

HardwareEvents events
This field is a list of event names or groups of comma separated event
names. This option requires EventList option to be configured.

Cores cores groups
All events are reported on a per core basis. Monitoring of the events
can be configured for a group of cores (aggregated statistics). This
field defines groups of cores on which to monitor supported events. The
field is represented as list of strings with core group values. Each
string represents a list of cores in a group. If a group is enclosed in
square brackets each core is added individually to a separate group
(that is statistics are not aggregated). Allowed formats are:
0,1,2,3
0-10,20-18
1,3,5-8,10,0x10-12
[4-15,32-63]

If an empty string is provided as value for this field default cores
configuration is applied - that is separate group is created for each
core.

DispatchMultiPmu false|true
Enable or disable dispatching of cloned multi PMU for uncore events. If
disabled only total sum is dispatched as single event. If enabled sepa-
rate metric is dispatched for every counter.

Plugin "intel_rdt"
The intel_rdt plugin collects information provided by monitoring features
of Intel Resource Director Technology (Intel(R) RDT) like Cache Monitoring
Technology (CMT), Memory Bandwidth Monitoring (MBM). These features provide
information about utilization of shared resources. CMT monitors last level
cache occupancy (LLC). MBM supports two types of events reporting local and
remote memory bandwidth. Local memory bandwidth (MBL) reports the bandwidth
of accessing memory associated with the local socket. Remote memory band-
width (MBR) reports the bandwidth of accessing the remote socket. Also this
technology allows to monitor instructions per clock (IPC). Monitor events
are hardware dependant. Monitoring capabilities are detected on plugin ini-
tialization and only supported events are monitored.

Note: intel_rdt plugin is using model-specific registers (MSRs), which re-
quire an additional capability to be enabled if collectd is run as a ser-
vice. Please refer to contrib/systemd.collectd.service file for more de-
tails.

Synopsis:

<Plugin "intel_rdt">
Cores "0-2" "3,4,6" "8-10,15"
Processes "sshd,qemu-system-x86" "bash"
</Plugin>

Options:

Interval seconds
The interval within which to retrieve statistics on monitored events in
seconds. For milliseconds divide the time by 1000 for example if the
desired interval is 50ms, set interval to 0.05. Due to limited capacity
of counters it is not recommended to set interval higher than 1 sec.

Cores cores groups
Monitoring of the events can be configured for group of cores (aggre-
gated statistics). This field defines groups of cores on which to moni-
tor supported events. The field is represented as list of strings with
core group values. Each string represents a list of cores in a group.
Allowed formats are:
0,1,2,3
0-10,20-18
1,3,5-8,10,0x10-12

If an empty string is provided as value for this field default cores
configuration is applied - a separate group is created for each core.

Processes process names groups
Monitoring of the events can be configured for group of processes (ag-
gregated statistics). This field defines groups of processes on which
to monitor supported events. The field is represented as list of
strings with process names group values. Each string represents a list
of processes in a group. Allowed format is:
sshd,bash,qemu

Note: By default global interval is used to retrieve statistics on moni-
tored events. To configure a plugin specific interval use Interval option
of the intel_rdt <LoadPlugin> block. For milliseconds divide the time by
1000 for example if the desired interval is 50ms, set interval to 0.05.
Due to limited capacity of counters it is not recommended to set interval
higher than 1 sec.

Plugin "interface"
Interface Interface
Select this interface. By default these interfaces will then be col-
lected. For a more detailed description see IgnoreSelected below.

See /"IGNORELISTS" for details.

IgnoreSelected true|false
If no configuration is given, the interface-plugin will collect data
from all interfaces. This may not be practical, especially for loop-
back- and similar interfaces. Thus, you can use the Interface-option to
pick the interfaces you're interested in. Sometimes, however, it's eas-
ier/preferred to collect all interfaces except a few ones. This option
enables you to do that: By setting IgnoreSelected to true the effect of
Interface is inverted: All selected interfaces are ignored and all
other interfaces are collected.

It is possible to use regular expressions to match interface names, if
the name is surrounded by /.../ and collectd was compiled with support
for regexps. This is useful if there's a need to collect (or ignore)
data for a group of interfaces that are similarly named, without the
need to explicitly list all of them (especially useful if the list is
dynamic). Example:

Interface "lo"
Interface "/^veth/"
Interface "/^tun[0-9]+/"
IgnoreSelected "true"

This will ignore the loopback interface, all interfaces with names
starting with veth and all interfaces with names starting with tun fol-
lowed by at least one digit.

ReportInactive true|false
When set to false, only interfaces with non-zero traffic will be re-
ported. Note that the check is done by looking into whether a package
was sent at any time from boot and the corresponding counter is
non-zero. So, if the interface has been sending data in the past since
boot, but not during the reported time-interval, it will still be re-
ported.

The default value is true and results in collection of the data from
all interfaces that are selected by Interface and IgnoreSelected op-
tions.

UniqueName true|false
Interface name is not unique on Solaris (KSTAT), interface name is
unique only within a module/instance. Following tuple is considered
unique:
(ks_module, ks_instance, ks_name) If this option is set to true, in-
terface name contains above three fields separated by an underscore.
For more info on KSTAT, visit <http://docs.ora-
cle.com/cd/E23824_01/html/821-1468/kstat-3kstat.html#REFMAN3Ek-
stat-3kstat>

This option is only available on Solaris.

Plugin "ipmi"
The ipmi plugin allows to monitor server platform status using the Intelli-
gent Platform Management Interface (IPMI). Local and remote interfaces are
supported.

The plugin configuration consists of one or more Instance blocks which
specify one ipmi connection each. Each block requires one unique string ar-
gument as the instance name. If instances are not configured, an instance
with the default option values will be created.

For backwards compatibility, any option other than Instance block will
trigger legacy config handling and it will be treated as an option within
Instance block. This support will go away in the next major version of Col-
lectd.

Within the Instance blocks, the following options are allowed:

Address Address
Hostname or IP to connect to. If not specified, plugin will try to con-
nect to local management controller (BMC).

Username Username
Password Password
The username and the password to use for the connection to remote BMC.

AuthType MD5|rmcp+
Forces the authentication type to use for the connection to remote BMC.
By default most secure type is seleted.

Host Hostname
Sets the host field of dispatched values. Defaults to the global host-
name setting.

Sensor Sensor
Selects sensors to collect or to ignore, depending on IgnoreSelected.

See /"IGNORELISTS" for details.

IgnoreSelected true|false
If no configuration if given, the ipmi plugin will collect data from
all sensors found of type "temperature", "voltage", "current" and
"fanspeed". This option enables you to do that: By setting IgnoreSe-
lected to true the effect of Sensor is inverted: All selected sensors
are ignored and all other sensors are collected.

NotifySensorAdd true|false
If a sensor appears after initialization time of a minute a notifica-
tion is sent.

NotifySensorRemove true|false
If a sensor disappears a notification is sent.

NotifySensorNotPresent true|false
If you have for example dual power supply and one of them is
(un)plugged then a notification is sent.

NotifyIPMIConnectionState true|false
If a IPMI connection state changes after initialization time of a
minute a notification is sent. Defaults to false.

SELEnabled true|false
If system event log (SEL) is enabled, plugin will listen for sensor
threshold and discrete events. When event is received the notification
is sent. SEL event filtering can be configured using SELSensor and
SELIgnoreSelected config options. Defaults to false.

SELSensor SELSensor
Selects sensors to get events from or to ignore, depending on SELIg-
noreSelected.

See /"IGNORELISTS" for details.

SELIgnoreSelected true|false
If no configuration is given, the ipmi plugin will pass events from all
sensors. This option enables you to do that: By setting SELIgnoreSe-
lected to true the effect of SELSensor is inverted: All events from se-
lected sensors are ignored and all events from other sensors are
passed.

SELClearEvent true|false
If SEL clear event is enabled, plugin will delete event from SEL list
after it is received and successfully handled. In this case other tools
that are subscribed for SEL events will receive an empty event. De-
faults to false.

Plugin "ipstats"
This plugin collects counts for ipv4 and ipv6 various types of packets
passing through the system in total. At the moment it's only supported on
FreeBSD.

The full list of options available to include in the counted statistics is:
ip4receive IPv4 total packets received
ip4badsum IPv4 checksum bad
ip4tooshort IPv4 packet too short
ip4toosmall IPv4 not enough data
ip4badhlen IPv4 ip header length < data size
ip4badlen IPv4 ip length < ip header length
ip4fragment IPv4 fragments received
ip4fragdrop IPv4 frags dropped (dups, out of space)
ip4fragtimeout IPv4 fragments timed out
ip4forward IPv4 packets forwarded
ip4fastforward IPv4 packets fast forwarded
ip4cantforward IPv4 packets rcvd for unreachable dest
ip4redirectsent IPv4 packets forwarded on same net
ip4noproto IPv4 unknown or unsupported protocol
ip4deliver IPv4 datagrams delivered to upper level
ip4transmit IPv4 total ip packets generated here
ip4odrop IPv4 lost packets due to nobufs, etc.
ip4reassemble IPv4 total packets reassembled ok
ip4fragmented IPv4 datagrams successfully fragmented
ip4ofragment IPv4 output fragments created
ip4cantfrag IPv4 don't fragment flag was set, etc.
ip4badoptions IPv4 error in option processing
ip4noroute IPv4 packets discarded due to no route
ip4badvers IPv4 ip version != 4
ip4rawout IPv4 total raw ip packets generated
ip4toolong IPv4 ip length > max ip packet size
ip4notmember IPv4 multicasts for unregistered grps
ip4nogif IPv4 no match gif found
ip4badaddr IPv4 invalid address on header

ip6receive IPv6 total packets received
ip6tooshort IPv6 packet too short
ip6toosmall IPv6 not enough data
ip6fragment IPv6 fragments received
ip6fragdrop IPv6 frags dropped(dups, out of space)
ip6fragtimeout IPv6 fragments timed out
ip6fragoverflow IPv6 fragments that exceeded limit
ip6forward IPv6 packets forwarded
ip6cantforward IPv6 packets rcvd for unreachable dest
ip6redirectsent IPv6 packets forwarded on same net
ip6deliver IPv6 datagrams delivered to upper level
ip6transmit IPv6 total ip packets generated here
ip6odrop IPv6 lost packets due to nobufs, etc.
ip6reassemble IPv6 total packets reassembled ok
ip6fragmented IPv6 datagrams successfully fragmented
ip6ofragment IPv6 output fragments created
ip6cantfrag IPv6 don't fragment flag was set, etc.
ip6badoptions IPv6 error in option processing
ip6noroute IPv6 packets discarded due to no route
ip6badvers IPv6 ip6 version != 6
ip6rawout IPv6 total raw ip packets generated
ip6badscope IPv6 scope error
ip6notmember IPv6 don't join this multicast group
ip6nogif IPv6 no match gif found
ip6toomanyhdr IPv6 discarded due to too many headers

By default the following options are included in the counted packets:

- ip4receive - ip4forward - ip4transmit

- ip6receive - ip6forward - ip6transmit

For example to also count IPv4 and IPv6 fragments received, include the
following configuration:

<Plugin ipstats>
ip4fragment true
ip6fragment true
</Plugin>

Plugin "iptables"
Chain Table Chain [Comment|Number [Name]]
Chain6 Table Chain [Comment|Number [Name]]
Select the iptables/ip6tables filter rules to count packets and bytes
from.

If only Table and Chain are given, this plugin will collect the coun-
ters of all rules which have a comment-match. The comment is then used
as type-instance.

If Comment or Number is given, only the rule with the matching comment
or the nth rule will be collected. Again, the comment (or the number)
will be used as the type-instance.

If Name is supplied, it will be used as the type-instance instead of
the comment or the number.

Plugin "irq"
Irq Irq
Select this irq. By default these irqs will then be collected. For a
more detailed description see IgnoreSelected below.

See /"IGNORELISTS" for details.

IgnoreSelected true|false
If no configuration if given, the irq-plugin will collect data from all
irqs. This may not be practical, especially if no interrupts happen.
Thus, you can use the Irq-option to pick the interrupt you're inter-
ested in. Sometimes, however, it's easier/preferred to collect all in-
terrupts except a few ones. This option enables you to do that: By set-
ting IgnoreSelected to true the effect of Irq is inverted: All selected
interrupts are ignored and all other interrupts are collected.

Plugin "java"
The Java plugin makes it possible to write extensions for collectd in Java.
This section only discusses the syntax and semantic of the configuration
options. For more in-depth information on the Java plugin, please read col-
lectd-java(5).

Synopsis:

<Plugin "java">
JVMArg "-verbose:jni"
JVMArg "-Djava.class.path=/opt/collectd/lib/collectd/bindings/java"
LoadPlugin "org.collectd.java.Foobar"
<Plugin "org.collectd.java.Foobar">
# To be parsed by the plugin
</Plugin>
</Plugin>

Available configuration options:

JVMArg Argument
Argument that is to be passed to the Java Virtual Machine (JVM). This
works exactly the way the arguments to the java binary on the command
line work. Execute "java --help" for details.

Please note that all these options must appear before (i. e. above) any
other options! When another option is found, the JVM will be started
and later options will have to be ignored!

LoadPlugin JavaClass
Instantiates a new JavaClass object. The constructor of this object
very likely then registers one or more callback methods with the
server.

See collectd-java(5) for details.

When the first such option is found, the virtual machine (JVM) is cre-
ated. This means that all JVMArg options must appear before (i. e.
above) all LoadPlugin options!

Plugin Name
The entire block is passed to the Java plugin as an org.col-
lectd.api.OConfigItem object.

For this to work, the plugin has to register a configuration callback
first, see "config callback" in collectd-java(5). This means, that the
Plugin block must appear after the appropriate LoadPlugin block. Also
note, that Name depends on the (Java) plugin registering the callback
and is completely independent from the JavaClass argument passed to
LoadPlugin.

Plugin "load"
The Load plugin collects the system load. These numbers give a rough
overview over the utilization of a machine. The system load is defined as
the number of runnable tasks in the run-queue and is provided by many oper-
ating systems as a one, five or fifteen minute average.

The following configuration options are available:

ReportRelative false|true
When enabled, system load divided by number of available CPU cores is
reported for intervals 1 min, 5 min and 15 min. Defaults to false.

Plugin "logfile"
LogLevel debug|info|notice|warning|err
Sets the log-level. If, for example, set to notice, then all events
with severity notice, warning, or err will be written to the logfile.

Please note that debug is only available if collectd has been compiled
with debugging support.

File File
Sets the file to write log messages to. The special strings stdout and
stderr can be used to write to the standard output and standard error
channels, respectively. This, of course, only makes much sense when
collectd is running in foreground- or non-daemon-mode.

Timestamp true|false
Prefix all lines printed by the current time. Defaults to true.

PrintSeverity true|false
When enabled, all lines are prefixed by the severity of the log mes-
sage, for example "warning". Defaults to false.

Note: There is no need to notify the daemon after moving or removing the
log file (e. g. when rotating the logs). The plugin reopens the file for
each line it writes.

Plugin "logparser"
The logparser plugin is used to parse different kinds of logs. Setting
proper options you can choose strings to collect. Plugin searches the log
file for messages which contain several matches (two or more). When all
mandatory matches are found then it sends proper notification containing
all fetched values.

Synopsis:

<Plugin logparser>
<Logfile "/var/log/syslog">
FirstFullRead false
<Message "pcie_errors">
DefaultType "pcie_error"
DefaultSeverity "warning"
<Match "aer error">
Regex "AER:.*error received"
SubmatchIdx -1
</Match>
<Match "incident time">
Regex "(... .. ..:..:..) .* pcieport.*AER"
SubmatchIdx 1
IsMandatory false
</Match>
<Match "root port">
Regex "pcieport (.*): AER:"
SubmatchIdx 1
IsMandatory true
</Match>
<Match "device">
PluginInstance true
Regex " ([0-9a-fA-F:\\.]*): PCIe Bus Error"
SubmatchIdx 1
IsMandatory false
</Match>
<Match "severity_mandatory">
Regex "severity="
SubMatchIdx -1
</Match>
<Match "nonfatal">
Regex "severity=.*\\([nN]on-[fF]atal"
TypeInstance "non_fatal"
IsMandatory false
</Match>
<Match "fatal">
Regex "severity=.*\\([fF]atal"
Severity "failure"
TypeInstance "fatal"
IsMandatory false
</Match>
<Match "corrected">
Regex "severity=Corrected"
TypeInstance "correctable"
IsMandatory false
</Match>
<Match "error type">
Regex "type=(.*),"
SubmatchIdx 1
IsMandatory false
</Match>
<Match "id">
Regex ", id=(.*)"
SubmatchIdx 1
</Match>
</Message>
</Logfile>
</Plugin>

Options:

Logfile File
The Logfile block defines file to search. It may contain one or more
Message blocks which are defined below.

FirstFullRead true|false
Set to true if the file has to be parsed from the beginning on the
first read. If false only subsequent writes to log file will be
parsed.

Message Name
Message block contains matches to search the log file for. Each Message
block builds a notification message using matched elements if its
mandatory Match blocks are matched.

DefaultPluginInstance String
Sets the default value for the plugin instance of the notification.

DefaultType String
Sets the default value for the type of the notification.

DefaultTypeInstance String
Sets the default value for the type instance of the notification.

DefaultSeverity String
Sets the default severity. Must be set to "OK", "WARNING" or "FAILURE".
Default value is "OK".

Match Name
Multiple Match blocks define regular expression patterns for extracting
or excluding specific string patterns from parsing. First and last
Match items in the same Message set boundaries of multiline message and
are mandatory. If these matches are not found then the whole message
is discarded.

Regex Regex
Regular expression with pattern matching string. It may contain subex-
pressions, so next option SubmatchIdx specifies which subexpression
should be stored.

SubmatchIdx Integer
Index of subexpression to be used for notification. Multiple subexpres-
sions are allowed. Index value 0 takes whole regular expression match
as a result. Index value -1 does not add result to message item. Can
be omitted, default value is 0.

Excluderegex Regex
Regular expression for excluding lines containing specific matching
strings. This is processed before checking Regex pattern. It is op-
tional and can be omitted.

IsMandatory true|false
Flag indicating if Match item is mandatory for message validation. If
set to true, whole message is discarded if it's missing. For false its
presence is optional. Default value is set to true.

PluginInstance true|String
If set to true, it sets plugin instance to string returned by regex. It
can be overridden by user string.

Type true|String
Sets notification type using rules like PluginInstance.

TypeInstance true|String
Sets notification type instance using rules like above.

Severity String
Sets notification severity to one of the options: "OK", "WARNING",
"FAILURE".

Plugin "log_logstash"
The log logstash plugin behaves like the logfile plugin but formats mes-
sages as JSON events for logstash to parse and input.

LogLevel debug|info|notice|warning|err
Sets the log-level. If, for example, set to notice, then all events
with severity notice, warning, or err will be written to the logfile.

Please note that debug is only available if collectd has been compiled
with debugging support.

Note: There is no need to notify the daemon after moving or removing the
log file (e. g. when rotating the logs). The plugin reopens the file for
each line it writes.

Plugin "lpar"
The LPAR plugin reads CPU statistics of Logical Partitions, a virtualiza-
tion technique for IBM POWER processors. It takes into account CPU time
stolen from or donated to a partition, in addition to the usual user, sys-
tem, I/O statistics.

The following configuration options are available:

CpuPoolStats false|true
When enabled, statistics about the processor pool are read, too. The
partition needs to have pool authority in order to be able to acquire
this information. Defaults to false.

ReportBySerial false|true
If enabled, the serial of the physical machine the partition is cur-
rently running on is reported as hostname and the logical hostname of
the machine is reported in the plugin instance. Otherwise, the logical
hostname will be used (just like other plugins) and the plugin instance
will be empty. Defaults to false.

Plugin "lua"
This plugin embeds a Lua interpreter into collectd and provides an inter-
face to collectd's plugin system. See collectd-lua(5) for its documenta-
tion.

Plugin "mbmon"
The "mbmon plugin" uses mbmon to retrieve temperature, voltage, etc.

Be default collectd connects to localhost (127.0.0.1), port 411/tcp. The
Host and Port options can be used to change these values, see below. "mb-
mon" has to be running to work correctly. If "mbmon" is not running time-
outs may appear which may interfere with other statistics..

"mbmon" must be run with the -r option ("print TAG and Value format"); De-
bian's /etc/init.d/mbmon script already does this, other people will need
to ensure that this is the case.

Host Hostname
Hostname to connect to. Defaults to 127.0.0.1.

Port Port
TCP-Port to connect to. Defaults to 411.

Plugin "mdevents "
The mdevents plugin collects status changes from md (Linux software RAID)
devices.

RAID arrays are meant to allow users/administrators to keep systems up and
running, in case of common hardware problems (disk failure). Mdadm is the
standard software RAID management tool for Linux. It provides the ability
to monitor "metadata event" occurring such as disk failures, clean-to-dirty
transitions, and etc. The kernel provides the ability to report such ac-
tions to the userspace via sysfs, and mdadm takes action accordingly with
the monitoring capability. The mdmon polls the /sys looking for changes in
the entries array_state, sync_action, and per disk state attribute files.
This is meaningful for RAID1, 5 and 10 only.

Mdevents plugin is based on gathering RAID array events that are written to
syslog by mdadm. After registering an event, it can send a collectd notifi-
cation that contains mdadm event's data. Event consists of event type, raid
array name and, for particular events, name of component device.

Example message:

"Jan 17 05:24:27 pc1 mdadm[188]: NewArray event detected on md device
/dev/md0"

Plugin also classifies gathered event. This means that a notification will
have a different severity {OKAY, WARNING, FAILURE} for particular mdadm
event.

For proper work, mdevents plugin needs syslog and mdadm utilities to be
present on the running system. Otherwise it will not be compiled as a part
of collectd.

Synopsis:

<Plugin mdevents>
Event ""
IgnoreEvent False
Array ""
IgnoreArray False
</Plugin>

Plugin configuration:

Mdevents plugin's configuration is mostly based on IgnoreList, which is a
collectd's utility. User can specify what particular events/RAID arrays lie
in his interest. Setting of IgnoreEvent/IgnoreArray booleans won't take
effect if Event/Array config lists are empty - plugin will accept entry
anyway.

Options:

Event "EventName"
Names of events to be monitored, separated by spaces. Possible events
include:

User should set the events that should be monitored as a strings sepa-
rated by spaces, for example Events "DeviceDisappeared Fail DegradedAr-
ray".

IgnoreEvent false|true
If IgnoreEvent is set to true, events specified in Events will be ig-
nored. If it's false, only specified events will be monitored.

Array arrays
User can specify an array or a group of arrays using regexp. Plugin
will accept only RAID arrays names that start with "/dev/md".

IgnoreArray false|true
If IgnoreArray is set to true, arrays specified in Array will be ig-
nored. If it's false, only specified events will be monitored.

Plugin "mcelog"
The "mcelog plugin" uses mcelog to retrieve machine check exceptions.

By default the plugin connects to "/var/run/mcelog-client" to check if the
mcelog server is running. When the server is running, the plugin will tail
the specified logfile to retrieve machine check exception information and
send a notification with the details from the logfile. The plugin will use
the mcelog client protocol to retrieve memory related machine check excep-
tions. Note that for memory exceptions, notifications are only sent when
there is a change in the number of corrected/uncorrected memory errors.

The Memory block

Note: these options cannot be used in conjunction with the logfile options,
they are mutually exclusive.

McelogClientSocket Path Connect to the mcelog client socket using the UNIX
domain socket at Path. Defaults to "/var/run/mcelog-client".
PersistentNotification true|false Override default configuration to only
send notifications when sent when there is a change in the number of cor-
rected/uncorrected memory errors. When set to true notifications will be
sent for every read cycle. Default is false. Does not affect the stats be-
ing dispatched.

McelogLogfile Path
The mcelog file to parse. Defaults to "/var/log/mcelog". Note: this op-
tion cannot be used in conjunction with the memory block options, they
are mutually exclusive.

Plugin "md"
The "md plugin" collects information from Linux Software-RAID devices (md).

All reported values are of the type "md_disks". Reported type instances are
active, failed (present but not operational), spare (hot stand-by) and
missing (physically absent) disks.

Device Device
Select md devices based on device name. The device name is the basename
of the device, i.e. the name of the block device without the leading
"/dev/". See IgnoreSelected for more details.

See /"IGNORELISTS" for details.

IgnoreSelected true|false
Invert device selection: If set to true, all md devices except those
listed using Device are collected. If false (the default), only those
listed are collected. If no configuration is given, the md plugin will
collect data from all md devices.

Plugin "memcachec"
The "memcachec plugin" connects to a memcached server, queries one or more
given pages and parses the returned data according to user specification.
The matches used are the same as the matches used in the "curl" and "tail"
plugins.

In order to talk to the memcached server, this plugin uses the libmemcached
library. Please note that there is another library with a very similar
name, libmemcache (notice the missing `d'), which is not applicable.

Synopsis of the configuration:

<Plugin "memcachec">
<Page "plugin_instance">
Server "localhost"
Key "page_key"
Plugin "plugin_name"
<Match>
Regex "(\\d+) bytes sent"
DSType CounterAdd
Type "ipt_octets"
Instance "type_instance"
</Match>
</Page>
</Plugin>

The configuration options are:

<Page Name>
Each Page block defines one page to be queried from the memcached
server. The block requires one string argument which is used as plugin
instance.

Server Address
Sets the server address to connect to when querying the page. Must be
inside a Page block.

Key Key
When connected to the memcached server, asks for the page Key.

Plugin Plugin
Use Plugin as the plugin name when submitting values. Defaults to
"memcachec".

<Match>
Match blocks define which strings to look for and how matches sub-
strings are interpreted. For a description of match blocks, please see
"Plugin tail".

Plugin "memcached"
The memcached plugin connects to a memcached server and queries statistics
about cache utilization, memory and bandwidth used. <http://mem-
cached.org/>

<Plugin "memcached">
<Instance "name">
#Host "memcache.example.com"
Address "127.0.0.1"
Port 11211
</Instance>
</Plugin>

The plugin configuration consists of one or more Instance blocks which
specify one memcached connection each. Within the Instance blocks, the fol-
lowing options are allowed:

Host Hostname
Sets the host field of dispatched values. Defaults to the global host-
name setting. For backwards compatibility, values are also dispatched
with the global hostname when Host is set to 127.0.0.1 or localhost and
Address is not set.

Address Address
Hostname or IP to connect to. For backwards compatibility, defaults to
the value of Host or 127.0.0.1 if Host is unset.

Port Port
TCP port to connect to. Defaults to 11211.

Socket Path
Connect to memcached using the UNIX domain socket at Path. If this set-
ting is given, the Address and Port settings are ignored.

Plugin "mic"
The mic plugin gathers CPU statistics, memory usage and temperatures from
Intel's Many Integrated Core (MIC) systems.

Synopsis:

<Plugin mic>
ShowCPU true
ShowCPUCores true
ShowMemory true

ShowTemperatures true
Temperature vddg
Temperature vddq
IgnoreSelectedTemperature true

ShowPower true
Power total0
Power total1
IgnoreSelectedPower true
</Plugin>

The following options are valid inside the Plugin mic block:

ShowCPU true|false
If enabled (the default) a sum of the CPU usage across all cores is re-
ported.

ShowCPUCores true|false
If enabled (the default) per-core CPU usage is reported.

ShowMemory true|false
If enabled (the default) the physical memory usage of the MIC system is
reported.

ShowTemperatures true|false
If enabled (the default) various temperatures of the MIC system are re-
ported.

Temperature Name
This option controls which temperatures are being reported. Whether
matching temperatures are being ignored or only matching temperatures
are reported depends on the IgnoreSelectedTemperature setting below. By
default all temperatures are reported.

IgnoreSelectedTemperature false|true
Controls the behavior of the Temperature setting above. If set to false
(the default) only temperatures matching a Temperature option are re-
ported or, if no Temperature option is specified, all temperatures are
reported. If set to true, matching temperatures are ignored and all
other temperatures are reported.

Known temperature names are:

die Die of the CPU

devmem
Device Memory

fin Fan In

foutFan Out

vccpVoltage ccp

vddgVoltage ddg

vddqVoltage ddq

ShowPower true|false
If enabled (the default) various temperatures of the MIC system are re-
ported.

Power Name
This option controls which power readings are being reported. Whether
matching power readings are being ignored or only matching power read-
ings are reported depends on the IgnoreSelectedPower setting below. By
default all power readings are reported.

IgnoreSelectedPower false|true
Controls the behavior of the Power setting above. If set to false (the
default) only power readings matching a Power option are reported or,
if no Power option is specified, all power readings are reported. If
set to true, matching power readings are ignored and all other power
readings are reported.

Known power names are:

total0
Total power utilization averaged over Time Window 0 (uWatts).

total1
Total power utilization averaged over Time Window 0 (uWatts).

instInstantaneous power (uWatts).

imaxMax instantaneous power (uWatts).

pciePCI-E connector power (uWatts).

c2x32x3 connector power (uWatts).

c2x42x4 connector power (uWatts).

vccpCore rail (uVolts).

vddgUncore rail (uVolts).

vddqMemory subsystem rail (uVolts).

Plugin "memory"
The memory plugin provides the following configuration options:

ValuesAbsolute true|false
Enables or disables reporting of physical memory usage in absolute num-
bers, i.e. bytes. Defaults to true.

ValuesPercentage false|true
Enables or disables reporting of physical memory usage in percentages,
e.g. percent of physical memory used. Defaults to false.

This is useful for deploying collectd in a heterogeneous environment in
which the sizes of physical memory vary.

Plugin "modbus"
The modbus plugin connects to a Modbus "slave" via Modbus/TCP or Modbus/RTU
and reads register values. It supports reading single registers (unsigned
16 bit values), large integer values (unsigned 32 bit and 64 bit values)
and floating point values (two registers interpreted as IEEE floats in big
endian notation).

Synopsis:

<Data "voltage-input-1">
RegisterBase 0
RegisterType float
RegisterCmd ReadHolding
Type voltage
Instance "input-1"
#Scale 1.0
#Shift 0.0
</Data>

<Data "voltage-input-2">
RegisterBase 2
RegisterType float
RegisterCmd ReadHolding
Type voltage
Instance "input-2"
</Data>

<Data "supply-temperature-1">
RegisterBase 0
RegisterType Int16
RegisterCmd ReadHolding
Type temperature
Instance "temp-1"
</Data>

<Host "modbus.example.com">
Address "192.168.0.42"
Port "502"
Interval 60

<Slave 1>
Instance "power-supply"
Collect "voltage-input-1"
Collect "voltage-input-2"
</Slave>
</Host>

<Host "localhost">
Device "/dev/ttyUSB0"
Baudrate 38400
Interval 20

<Slave 1>
Instance "temperature"
Collect "supply-temperature-1"
</Slave>
</Host>

<Data Name> blocks
Data blocks define a mapping between register numbers and the "types"
used by collectd.

Within <Data /> blocks, the following options are allowed:

RegisterBase Number
Configures the base register to read from the device. If the option
RegisterType has been set to Uint32 or Float, this and the next
register will be read (the register number is increased by one).

RegisterType
Int16|Int32|Int64|Uint16|Uint32|UInt64|Float|Int32LE|Uint32LE|FloatLE
Specifies what kind of data is returned by the device. This de-
faults to Uint16. If the type is Int32, Int32LE, Uint32, Uint32LE,
Float or FloatLE, two 16 bit registers at RegisterBase and Regis-
terBase+1 will be read and the data is combined into one 32 value.
For Int32, Uint32 and Float the most significant 16 bits are in the
register at RegisterBase and the least significant 16 bits are in
the register at RegisterBase+1. For Int32LE, Uint32LE, or
Float32LE, the high and low order registers are swapped with the
most significant 16 bits in the RegisterBase+1 and the least sig-
nificant 16 bits in RegisterBase. If the type is Int64 or UInt64,
four 16 bit registers at RegisterBase, RegisterBase+1, Register-
Base+2 and RegisterBase+3 will be read and the data combined into
one 64 value.

RegisterCmd ReadHolding|ReadInput
Specifies register type to be collected from device. Works only
with libmodbus 2.9.2 or higher. Defaults to ReadHolding.

Type Type
Specifies the "type" (data set) to use when dispatching the value
to collectd. Currently, only data sets with exactly one data source
are supported.

Instance Instance
Sets the type instance to use when dispatching the value to In-
stance. If unset, an empty string (no type instance) is used.

Scale Value
The values taken from device are multiplied by Value. The field is
optional and the default is 1.0.

Shift Value
Value is added to values from device after they have been multi-
plied by Scale value. The field is optional and the default value
is 0.0.

<Host Name> blocks
Host blocks are used to specify to which hosts to connect and what data
to read from their "slaves". The string argument Name is used as host-
name when dispatching the values to collectd.

Within <Host /> blocks, the following options are allowed:

Address Hostname
For Modbus/TCP, specifies the node name (the actual network ad-
dress) used to connect to the host. This may be an IP address or a
hostname. Please note that the used libmodbus library only supports
IPv4 at the moment.

Port Service
for Modbus/TCP, specifies the port used to connect to the host. The
port can either be given as a number or as a service name. Please
note that the Service argument must be a string, even if ports are
given in their numerical form. Defaults to "502".

Device Devicenode
For Modbus/RTU, specifies the path to the serial device being used.

Baudrate Baudrate
For Modbus/RTU, specifies the baud rate of the serial device.
Note, connections currently support only 8/N/1.

UARTType UARTType
For Modbus/RTU, specifies the type of the serial device. RS232,
RS422 and RS485 are supported. Defaults to RS232. Available only
on Linux systems with libmodbus>=2.9.4.

Interval Interval
Sets the interval (in seconds) in which the values will be col-
lected from this host. By default the global Interval setting will
be used.

<Slave ID>
Over each connection, multiple Modbus devices may be reached. The
slave ID is used to specify which device should be addressed. For
each device you want to query, one Slave block must be given.

Within <Slave /> blocks, the following options are allowed:

Instance Instance
Specify the plugin instance to use when dispatching the values
to collectd. By default "slave_ID" is used.

Collect DataName
Specifies which data to retrieve from the device. DataName must
be the same string as the Name argument passed to a Data block.
You can specify this option multiple times to collect more than
one value from a slave. At least one Collect option is manda-
tory.

Plugin "mqtt"
The MQTT plugin can send metrics to MQTT (Publish blocks) and receive val-
ues from MQTT (Subscribe blocks).

Synopsis:

<Plugin mqtt>
<Publish "name">
Host "mqtt.example.com"
Prefix "collectd"
</Publish>
<Subscribe "name">
Host "mqtt.example.com"
Topic "collectd/#"
</Subscribe>
</Plugin>

The plugin's configuration is in Publish and/or Subscribe blocks, configur-
ing the sending and receiving direction respectively. The plugin will reg-
ister a write callback named "mqtt/name" where name is the string argument
given to the Publish block. Both types of blocks share many but not all of
the following options. If an option is valid in only one of the blocks, it
will be mentioned explicitly.

Options:

Host Hostname
Hostname of the MQTT broker to connect to.

Port Service
Port number or service name of the MQTT broker to connect to.

User UserName
Username used when authenticating to the MQTT broker.

Password Password
Password used when authenticating to the MQTT broker.

ClientId ClientId
MQTT client ID to use. Defaults to the hostname used by collectd.

QoS [0-2]
Sets the Quality of Service, with the values 0, 1 and 2 meaning:

0 At most once

1 At least once

2 Exactly once

In Publish blocks, this option determines the QoS flag set on outgoing
messages and defaults to 0. In Subscribe blocks, determines the maximum
QoS setting the client is going to accept and defaults to 2. If the QoS
flag on a message is larger than the maximum accepted QoS of a sub-
scriber, the message's QoS will be downgraded.

Prefix Prefix (Publish only)
This plugin will use one topic per value list which will looks like a
path. Prefix is used as the first path element and defaults to col-
lectd.

An example topic name would be:

collectd/cpu-0/cpu-user

Retain false|true (Publish only)
Controls whether the MQTT broker will retain (keep a copy of) the last
message sent to each topic and deliver it to new subscribers. Defaults
to false.

StoreRates true|false (Publish only)
Controls whether "DERIVE" and "COUNTER" metrics are converted to a rate
before sending. Defaults to true.

CleanSession true|false (Subscribe only)
Controls whether the MQTT "cleans" the session up after the subscriber
disconnects or if it maintains the subscriber's subscriptions and all
messages that arrive while the subscriber is disconnected. Defaults to
true.

Topic TopicName (Subscribe only)
Configures the topic(s) to subscribe to. You can use the single level
"+" and multi level "#" wildcards. Defaults to collectd/#, i.e. all
topics beneath the collectd branch.

CACert file
Path to the PEM-encoded CA certificate file. Setting this option en-
ables TLS communication with the MQTT broker, and as such, Port should
be the TLS-enabled port of the MQTT broker. This option enables the
use of TLS.

CertificateFile file
Path to the PEM-encoded certificate file to use as client certificate
when connecting to the MQTT broker. Only valid if CACert and Certifi-
cateKeyFile are also set.

CertificateKeyFile file
Path to the unencrypted PEM-encoded key file corresponding to Certifi-
cateFile. Only valid if CACert and CertificateFile are also set.

TLSProtocol protocol
If configured, this specifies the string protocol version (e.g.
"tlsv1", "tlsv1.2") to use for the TLS connection to the broker. If not
set a default version is used which depends on the version of OpenSSL
the Mosquitto library was linked against. Only valid if CACert is set.

CipherSuite ciphersuite
A string describing the ciphers available for use. See ciphers(1) and
the "openssl ciphers" utility for more information. If unset, the de-
fault ciphers will be used. Only valid if CACert is set.

Plugin "mysql"
The "mysql plugin" requires mysqlclient to be installed. It connects to one
or more databases when started and keeps the connection up as long as pos-
sible. When the connection is interrupted for whatever reason it will try
to re-connect. The plugin will complain loudly in case anything goes wrong.

This plugin issues the MySQL "SHOW STATUS" / "SHOW GLOBAL STATUS" command
and collects information about MySQL network traffic, executed statements,
requests, the query cache and threads by evaluating the "Bytes_{re-
ceived,sent}", "Com_*", "Handler_*", "Qcache_*" and "Threads_*" return val-
ues. Please refer to the MySQL reference manual, 5.1.6. Server Status Vari-
ables for an explanation of these values.

Optionally, master and slave statistics may be collected in a MySQL repli-
cation setup. In that case, information about the synchronization state of
the nodes are collected by evaluating the "Position" return value of the
"SHOW MASTER STATUS" command and the "Seconds_Behind_Master", "Read_Mas-
ter_Log_Pos" and "Exec_Master_Log_Pos" return values of the "SHOW SLAVE
STATUS" command. See the MySQL reference manual, 12.5.5.21 SHOW MASTER STA-
TUS Syntax and 12.5.5.31 SHOW SLAVE STATUS Syntax for details.

Synopsis:

<Plugin mysql>
<Database foo>
Host "hostname"
User "username"
Password "password"
Port "3306"
MasterStats true
ConnectTimeout 10
SSLKey "/path/to/key.pem"
SSLCert "/path/to/cert.pem"
SSLCA "/path/to/ca.pem"
SSLCAPath "/path/to/cas/"
SSLCipher "DHE-RSA-AES256-SHA"
</Database>

<Database bar>
Alias "squeeze"
Host "localhost"
Socket "/var/run/mysql/mysqld.sock"
SlaveStats true
SlaveNotifications true
</Database>

<Database galera>
Alias "galera"
Host "localhost"
Socket "/var/run/mysql/mysqld.sock"
WsrepStats true
</Database>
</Plugin>

A Database block defines one connection to a MySQL database. It accepts a
single argument which specifies the name of the database. None of the other
options are required. MySQL will use default values as documented in the
"mysql_real_connect()" and "mysql_ssl_set()" sections in the MySQL refer-
ence manual.

Alias Alias
Alias to use as sender instead of hostname when reporting. This may be
useful when having cryptic hostnames.

Host Hostname
Hostname of the database server. Defaults to localhost.

User Username
Username to use when connecting to the database. The user does not have
to be granted any privileges (which is synonym to granting the "USAGE"
privilege), unless you want to collect replication statistics (see Mas-
terStats and SlaveStats below). In this case, the user needs the
"REPLICATION CLIENT" (or "SUPER") privileges. Else, any existing MySQL
user will do.

Password Password
Password needed to log into the database.

Database Database
Select this database. Defaults to no database which is a perfectly rea-
sonable option for what this plugin does.

Port Port
TCP-port to connect to. The port must be specified in its numeric form,
but it must be passed as a string nonetheless. For example:

Port "3306"

If Host is set to localhost (the default), this setting has no effect.
See the documentation for the "mysql_real_connect" function for de-
tails.

Socket Socket
Specifies the path to the UNIX domain socket of the MySQL server. This
option only has any effect, if Host is set to localhost (the default).
Otherwise, use the Port option above. See the documentation for the
"mysql_real_connect" function for details.

InnodbStats true|false
If enabled, metrics about the InnoDB storage engine are collected.
Disabled by default.

MasterStats true|false
SlaveStats true|false
Enable the collection of master / slave statistics in a replication
setup. In order to be able to get access to these statistics, the user
needs special privileges. See the User documentation above. Defaults to
false.

SlaveNotifications true|false
If enabled, the plugin sends a notification if the replication slave
I/O and / or SQL threads are not running. Defaults to false.

WsrepStats true|false
Enable the collection of wsrep plugin statistics, used in Master-Master
replication setups like in MySQL Galera/Percona XtraDB Cluster. User
needs only privileges to execute 'SHOW GLOBAL STATUS'. Defaults to
false.

ConnectTimeout Seconds
Sets the connect timeout for the MySQL client.

SSLKey Path
If provided, the X509 key in PEM format.

SSLCert Path
If provided, the X509 cert in PEM format.

SSLCA Path
If provided, the CA file in PEM format (check OpenSSL docs).

SSLCAPath Path
If provided, the CA directory (check OpenSSL docs).

SSLCipher String
If provided, the SSL cipher to use.

Plugin "netapp"
The netapp plugin can collect various performance and capacity information
from a NetApp filer using the NetApp API.

Please note that NetApp has a wide line of products and a lot of different
software versions for each of these products. This plugin was developed for
a NetApp FAS3040 running OnTap 7.2.3P8 and tested on FAS2050 7.3.1.1L1,
FAS3140 7.2.5.1 and FAS3020 7.2.4P9. It should work for most combinations
of model and software version but it is very hard to test this. If you
have used this plugin with other models and/or software version, feel free
to send us a mail to tell us about the results, even if it's just a short
"It works".

To collect these data collectd will log in to the NetApp via HTTP(S) and
HTTP basic authentication.

Do not use a regular user for this! Create a special collectd user with
just the minimum of capabilities needed. The user only needs the "lo-
gin-http-admin" capability as well as a few more depending on which data
will be collected. Required capabilities are documented below.

Synopsis

<Plugin "netapp">
<Host "netapp1.example.com">
Protocol "https"
Address "10.0.0.1"
Port 443
User "username"
Password "aef4Aebe"
Interval 30

<WAFL>
Interval 30
GetNameCache true
GetDirCache true
GetBufferCache true
GetInodeCache true
</WAFL>

<Disks>
Interval 30
GetBusy true
</Disks>

<VolumePerf>
Interval 30
GetIO "volume0"
IgnoreSelectedIO false
GetOps "volume0"
IgnoreSelectedOps false
GetLatency "volume0"
IgnoreSelectedLatency false
</VolumePerf>

<VolumeUsage>
Interval 30
GetCapacity "vol0"
GetCapacity "vol1"
IgnoreSelectedCapacity false
GetSnapshot "vol1"
GetSnapshot "vol3"
IgnoreSelectedSnapshot false
</VolumeUsage>

<Quota>
Interval 60
</Quota>

<Snapvault>
Interval 30
</Snapvault>

<System>
Interval 30
GetCPULoad true
GetInterfaces true
GetDiskOps true
GetDiskIO true
</System>

<VFiler vfilerA>
Interval 60

SnapVault true
# ...
</VFiler>
</Host>
</Plugin>

The netapp plugin accepts the following configuration options:

Host Name
A host block defines one NetApp filer. It will appear in collectd with
the name you specify here which does not have to be its real name nor
its hostname (see the Address option below).

VFiler Name
A VFiler block may only be used inside a host block. It accepts all the
same options as the Host block (except for cascaded VFiler blocks) and
will execute all NetApp API commands in the context of the specified
VFiler(R). It will appear in collectd with the name you specify here
which does not have to be its real name. The VFiler name may be speci-
fied using the VFilerName option. If this is not specified, it will de-
fault to the name you specify here.

The VFiler block inherits all connection related settings from the sur-
rounding Host block (which appear before the VFiler block) but they may
be overwritten inside the VFiler block.

This feature is useful, for example, when using a VFiler as SnapVault
target (supported since OnTap 8.1). In that case, the SnapVault statis-
tics are not available in the host filer (vfiler0) but only in the re-
spective VFiler context.

Protocol httpd|http
The protocol collectd will use to query this host.

Optional

Type: string

Default: https

Valid options: http, https

Address Address
The hostname or IP address of the host.

Optional

Type: string

Default: The "host" block's name.

Port Port
The TCP port to connect to on the host.

Optional

Type: integer

Default: 80 for protocol "http", 443 for protocol "https"

User User
Password Password
The username and password to use to login to the NetApp.

Mandatory

Type: string

VFilerName Name
The name of the VFiler in which context to execute API commands. If not
specified, the name provided to the VFiler block will be used instead.

Optional

Type: string

Default: name of the VFiler block

Note: This option may only be used inside VFiler blocks.

Interval Interval
TODO

The following options decide what kind of data will be collected. You can
either use them as a block and fine tune various parameters inside this
block, use them as a single statement to just accept all default values, or
omit it to not collect any data.

The following options are valid inside all blocks:

Interval Seconds
Collect the respective statistics every Seconds seconds. Defaults to
the host specific setting.

The System block

This will collect various performance data about the whole system.

Note: To get this data the collectd user needs the "api-perf-object-get-in-
stances" capability.

Interval Seconds
Collect disk statistics every Seconds seconds.

GetCPULoad true|false
If you set this option to true the current CPU usage will be read. This
will be the average usage between all CPUs in your NetApp without any
information about individual CPUs.

Note: These are the same values that the NetApp CLI command "sysstat"
returns in the "CPU" field.

Optional

Type: boolean

Default: true

Result: Two value lists of type "cpu", and type instances "idle" and
"system".

GetInterfaces true|false
If you set this option to true the current traffic of the network in-
terfaces will be read. This will be the total traffic over all inter-
faces of your NetApp without any information about individual inter-
faces.

Note: This is the same values that the NetApp CLI command "sysstat" re-
turns in the "Net kB/s" field.

Or is it?

Optional

Type: boolean

Default: true

Result: One value list of type "if_octects".

GetDiskIO true|false
If you set this option to true the current IO throughput will be read.
This will be the total IO of your NetApp without any information about
individual disks, volumes or aggregates.

Note: This is the same values that the NetApp CLI command "sysstat" re-
turns in the "Disk kB/s" field.

Optional

Type: boolean

Default: true

Result: One value list of type "disk_octets".

GetDiskOps true|false
If you set this option to true the current number of HTTP, NFS, CIFS,
FCP, iSCSI, etc. operations will be read. This will be the total number
of operations on your NetApp without any information about individual
volumes or aggregates.

Note: These are the same values that the NetApp CLI command "sysstat"
returns in the "NFS", "CIFS", "HTTP", "FCP" and "iSCSI" fields.

Optional

Type: boolean

Default: true

Result: A variable number of value lists of type "disk_ops_complex".
Each type of operation will result in one value list with the name of
the operation as type instance.

The WAFL block

This will collect various performance data about the WAFL file system. At
the moment this just means cache performance.

Note: To get this data the collectd user needs the "api-perf-object-get-in-
stances" capability.

Note: The interface to get these values is classified as "Diagnostics" by
NetApp. This means that it is not guaranteed to be stable even between mi-
nor releases.

Interval Seconds
Collect disk statistics every Seconds seconds.

GetNameCache true|false
Optional

Type: boolean

Default: true

Result: One value list of type "cache_ratio" and type instance
"name_cache_hit".

GetDirCache true|false
Optional

Type: boolean

Default: true

Result: One value list of type "cache_ratio" and type instance
"find_dir_hit".

GetInodeCache true|false
Optional

Type: boolean

Default: true

Result: One value list of type "cache_ratio" and type instance "in-
ode_cache_hit".

GetBufferCache true|false
Note: This is the same value that the NetApp CLI command "sysstat" re-
turns in the "Cache hit" field.

Optional

Type: boolean

Default: true

Result: One value list of type "cache_ratio" and type instance
"buf_hash_hit".

The Disks block

This will collect performance data about the individual disks in the Ne-
tApp.

Note: To get this data the collectd user needs the "api-perf-object-get-in-
stances" capability.

Interval Seconds
Collect disk statistics every Seconds seconds.

GetBusy true|false
If you set this option to true the busy time of all disks will be cal-
culated and the value of the busiest disk in the system will be writ-
ten.

Note: This is the same values that the NetApp CLI command "sysstat" re-
turns in the "Disk util" field. Probably.

Optional

Type: boolean

Default: true

Result: One value list of type "percent" and type instance "disk_busy".

The VolumePerf block

This will collect various performance data about the individual volumes.

You can select which data to collect about which volume using the following
options. They follow the standard ignorelist semantic.

Note: To get this data the collectd user needs the api-perf-object-get-in-
stances capability.

Interval Seconds
Collect volume performance data every Seconds seconds.

GetIO Volume
GetOps Volume
GetLatency Volume
Select the given volume for IO, operations or latency statistics col-
lection. The argument is the name of the volume without the "/vol/"
prefix.

Since the standard ignorelist functionality is used here, you can use a
string starting and ending with a slash to specify regular expression
matching: To match the volumes "vol0", "vol2" and "vol7", you can use
this regular expression:

GetIO "/^vol[027]$/"

If no regular expression is specified, an exact match is required.
Both, regular and exact matching are case sensitive.

If no volume was specified at all for either of the three options, that
data will be collected for all available volumes.

See /"IGNORELISTS" for details.

IgnoreSelectedIO true|false
IgnoreSelectedOps true|false
IgnoreSelectedLatency true|false
When set to true, the volumes selected for IO, operations or latency
statistics collection will be ignored and the data will be collected
for all other volumes.

When set to false, data will only be collected for the specified vol-
umes and all other volumes will be ignored.

If no volumes have been specified with the above Get* options, all vol-
umes will be collected regardless of the IgnoreSelected* option.

Defaults to false

The VolumeUsage block

This will collect capacity data about the individual volumes.

Note: To get this data the collectd user needs the api-volume-list-info ca-
pability.

Interval Seconds
Collect volume usage statistics every Seconds seconds.

GetCapacity VolumeName
The current capacity of the volume will be collected. This will result
in two to four value lists, depending on the configuration of the vol-
ume. All data sources are of type "df_complex" with the name of the
volume as plugin_instance.

There will be type_instances "used" and "free" for the number of used
and available bytes on the volume. If the volume has some space re-
served for snapshots, a type_instance "snap_reserved" will be avail-
able. If the volume has SIS enabled, a type_instance "sis_saved" will
be available. This is the number of bytes saved by the SIS feature.

Note: The current NetApp API has a bug that results in this value being
reported as a 32 bit number. This plugin tries to guess the correct
number which works most of the time. If you see strange values here,
bug NetApp support to fix this.

Repeat this option to specify multiple volumes.

IgnoreSelectedCapacity true|false
Specify whether to collect only the volumes selected by the GetCapacity
option or to ignore those volumes. IgnoreSelectedCapacity defaults to
false. However, if no GetCapacity option is specified at all, all ca-
pacities will be selected anyway.

GetSnapshot VolumeName
Select volumes from which to collect snapshot information.

Usually, the space used for snapshots is included in the space reported
as "used". If snapshot information is collected as well, the space used
for snapshots is subtracted from the used space.

To make things even more interesting, it is possible to reserve space
to be used for snapshots. If the space required for snapshots is less
than that reserved space, there is "reserved free" and "reserved used"
space in addition to "free" and "used". If the space required for snap-
shots exceeds the reserved space, that part allocated in the normal
space is subtracted from the "used" space again.

Repeat this option to specify multiple volumes.

IgnoreSelectedSnapshot
Specify whether to collect only the volumes selected by the GetSnapshot
option or to ignore those volumes. IgnoreSelectedSnapshot defaults to
false. However, if no GetSnapshot option is specified at all, all ca-
pacities will be selected anyway.

The Quota block

This will collect (tree) quota statistics (used disk space and number of
used files). This mechanism is useful to get usage information for single
qtrees. In case the quotas are not used for any other purpose, an entry
similar to the following in "/etc/quotas" would be sufficient:

/vol/volA/some_qtree tree - - - - -

After adding the entry, issue "quota on -w volA" on the NetApp filer.

Interval Seconds
Collect SnapVault(R) statistics every Seconds seconds.

The SnapVault block

This will collect statistics about the time and traffic of SnapVault(R)
transfers.

Interval Seconds
Collect SnapVault(R) statistics every Seconds seconds.

Plugin "netlink"
The "netlink" plugin uses a netlink socket to query the Linux kernel about
statistics of various interface and routing aspects.

Interface Interface
VerboseInterface Interface
Instruct the plugin to collect interface statistics. This is basically
the same as the statistics provided by the "interface" plugin (see
above) but potentially much more detailed.

When configuring with Interface only the basic statistics will be col-
lected, namely octets, packets, and errors. These statistics are col-
lected by the "interface" plugin, too, so using both at the same time
is no benefit.

When configured with VerboseInterface all counters except the basic
ones will be collected, so that no data needs to be collected twice if
you use the "interface" plugin. This includes dropped packets, re-
ceived multicast packets, collisions and a whole zoo of differentiated
RX and TX errors. You can try the following command to get an idea of
what awaits you:

ip -s -s link list

If Interface is All, all interfaces will be selected.

Interface "/^eth/"
Interface "/^ens[1-4]$|^enp[0-3]$/"
VerboseInterface "/^eno[0-9]+/"

This will match all interfaces with names starting with eth, all inter-
faces in range ens1 - ens4 and enp0 - enp3, and for verbose metrics all
interfaces with names starting with eno followed by at least one digit.

QDisc Interface [QDisc]
Class Interface [Class]
Filter Interface [Filter]
Collect the octets and packets that pass a certain qdisc, class or fil-
ter.

QDiscs and classes are identified by their type and handle (or clas-
sid). Filters don't necessarily have a handle, therefore the parent's
handle is used. The notation used in collectd differs from that used
in tc(1) in that it doesn't skip the major or minor number if it's zero
and doesn't print special ids by their name. So, for example, a qdisc
may be identified by "pfifo_fast-1:0" even though the minor number of
all qdiscs is zero and thus not displayed by tc(1).

If QDisc, Class, or Filter is given without the second argument, i. .e.
without an identifier, all qdiscs, classes, or filters that are associ-
ated with that interface will be collected.

Since a filter itself doesn't necessarily have a handle, the parent's
handle is used. This may lead to problems when more than one filter is
attached to a qdisc or class. This isn't nice, but we don't know how
this could be done any better. If you have a idea, please don't hesi-
tate to tell us.

As with the Interface option you can specify All as the interface,
meaning all interfaces.

Here are some examples to help you understand the above text more eas-
ily:

<Plugin netlink>
VerboseInterface "All"
QDisc "eth0" "pfifo_fast-1:0"
QDisc "ppp0"
Class "ppp0" "htb-1:10"
Filter "ppp0" "u32-1:0"
</Plugin>

See /"IGNORELISTS" for details.

IgnoreSelected
The behavior is the same as with all other similar plugins: If nothing
is selected at all, everything is collected. If some things are se-
lected using the options described above, only these statistics are
collected. If you set IgnoreSelected to true, this behavior is in-
verted, i. e. the specified statistics will not be collected.

CollectVFStats true|false
Allow plugin to collect VF's statistics if there are Virtual Functions
available for interfaces specified in Interface or VerboseInterface.
All available stats are collected no matter if parent interface is set
by Interface or VerboseInterface.

Plugin "network"
The Network plugin sends data to a remote instance of collectd, receives
data from a remote instance, or both at the same time. Data which has been
received from the network is usually not transmitted again, but this can be
activated, see the Forward option below.

The default IPv6 multicast group is "ff18::efc0:4a42". The default IPv4
multicast group is 239.192.74.66. The default UDP port is 25826.

Both, Server and Listen can be used as single option or as block. When used
as block, given options are valid for this socket only. The following exam-
ple will export the metrics twice: Once to an "internal" server (without
encryption and signing) and one to an external server (with cryptographic
signature):

<Plugin "network">
# Export to an internal server
# (demonstrates usage without additional options)
Server "collectd.internal.tld"

# Export to an external server
# (demonstrates usage with signature options)
<Server "collectd.external.tld">
SecurityLevel "sign"
Username "myhostname"
Password "ohl0eQue"
</Server>
</Plugin>

<Server Host [Port]>
The Server statement/block sets the server to send datagrams to. The
statement may occur multiple times to send each datagram to multiple
destinations.

The argument Host may be a hostname, an IPv4 address or an IPv6 ad-
dress. The optional second argument specifies a port number or a ser-
vice name. If not given, the default, 25826, is used.

The following options are recognized within Server blocks:

SecurityLevel Encrypt|Sign|None
Set the security you require for network communication. When the
security level has been set to Encrypt, data sent over the network
will be encrypted using AES-256. The integrity of encrypted packets
is ensured using SHA-1. When set to Sign, transmitted data is
signed using the HMAC-SHA-256 message authentication code. When set
to None, data is sent without any security.

This feature is only available if the network plugin was linked
with libgcrypt.

Username Username
Sets the username to transmit. This is used by the server to lookup
the password. See AuthFile below. All security levels except None
require this setting.

This feature is only available if the network plugin was linked
with libgcrypt.

Password Password
Sets a password (shared secret) for this socket. All security lev-
els except None require this setting.

This feature is only available if the network plugin was linked
with libgcrypt.

Interface Interface name
Set the outgoing interface for IP packets. This applies at least to
IPv6 packets and if possible to IPv4. If this option is not applic-
able, undefined or a non-existent interface name is specified, the
default behavior is to let the kernel choose the appropriate inter-
face. Be warned that the manual selection of an interface for uni-
cast traffic is only necessary in rare cases.

BindAddress IP Address
Set the outgoing IP address for IP packets. This option can be used
instead of the Interface option to explicitly define the IP address
which will be used to send Packets to the remote server.

ResolveInterval Seconds
Sets the interval at which to re-resolve the DNS for the Host. This
is useful to force a regular DNS lookup to support a high avail-
ability setup. If not specified, re-resolves are never attempted.

<Listen Host [Port]>
The Listen statement sets the interfaces to bind to. When multiple
statements are found the daemon will bind to multiple interfaces.

The argument Host may be a hostname, an IPv4 address or an IPv6 ad-
dress. If the argument is a multicast address the daemon will join that
multicast group. The optional second argument specifies a port number
or a service name. If not given, the default, 25826, is used.

The following options are recognized within "<Listen>" blocks:

SecurityLevel Encrypt|Sign|None
Set the security you require for network communication. When the
security level has been set to Encrypt, only encrypted data will be
accepted. The integrity of encrypted packets is ensured using
SHA-1. When set to Sign, only signed and encrypted data is ac-
cepted. When set to None, all data will be accepted. If an AuthFile
option was given (see below), encrypted data is decrypted if possi-
ble.

This feature is only available if the network plugin was linked
with libgcrypt.

AuthFile Filename
Sets a file in which usernames are mapped to passwords. These pass-
words are used to verify signatures and to decrypt encrypted net-
work packets. If SecurityLevel is set to None, this is optional. If
given, signed data is verified and encrypted packets are decrypted.
Otherwise, signed data is accepted without checking the signature
and encrypted data cannot be decrypted. For the other security
levels this option is mandatory.

The file format is very simple: Each line consists of a username
followed by a colon and any number of spaces followed by the pass-
word. To demonstrate, an example file could look like this:

user0: foo
user1: bar

Each time a packet is received, the modification time of the file
is checked using stat(2). If the file has been changed, the con-
tents is re-read. While the file is being read, it is locked using
fcntl(2).

Interface Interface name
Set the incoming interface for IP packets explicitly. This applies
at least to IPv6 packets and if possible to IPv4. If this option is
not applicable, undefined or a non-existent interface name is spec-
ified, the default behavior is, to let the kernel choose the appro-
priate interface. Thus incoming traffic gets only accepted, if it
arrives on the given interface.

TimeToLive 1-255
Set the time-to-live of sent packets. This applies to all, unicast and
multicast, and IPv4 and IPv6 packets. The default is to not change this
value. That means that multicast packets will be sent with a TTL of 1
(one) on most operating systems.

MaxPacketSize 1024-65535
Set the maximum size for datagrams received over the network. Packets
larger than this will be truncated. Defaults to 1452 bytes, which is
the maximum payload size that can be transmitted in one Ethernet frame
using IPv6 / UDP.

On the server side, this limit should be set to the largest value used
on any client. Likewise, the value on the client must not be larger
than the value on the server, or data will be lost.

Compatibility: Versions prior to version 4.8 used a fixed sized buffer
of 1024 bytes. Versions 4.8, 4.9 and 4.10 used a default value of
1024 bytes to avoid problems when sending data to an older server.

Forward true|false
If set to true, write packets that were received via the network plugin
to the sending sockets. This should only be activated when the Listen-
and Server-statements differ. Otherwise packets may be send multiple
times to the same multicast group. While this results in more network
traffic than necessary it's not a huge problem since the plugin has a
duplicate detection, so the values will not loop.

ReportStats true|false
The network plugin cannot only receive and send statistics, it can also
create statistics about itself. Collectd data included the number of
received and sent octets and packets, the length of the receive queue
and the number of values handled. When set to true, the Network plugin
will make these statistics available. Defaults to false.

Plugin "nfs"
The nfs plugin collects information about the usage of the Network File
System (NFS). It counts the number of procedure calls for each procedure,
grouped by version and whether the system runs as server or client.

It is possibly to omit metrics for a specific NFS version by setting one or
more of the following options to false (all of them default to true).

ReportV2 true|false
ReportV3 true|false
ReportV4 true|false

Plugin "nginx"
This plugin collects the number of connections and requests handled by the
"nginx daemon" (speak: engine X), a HTTP and mail server/proxy. It queries
the page provided by the "ngx_http_stub_status_module" module, which isn't
compiled by default. Please refer to <http://wiki.codemongers.com/NginxS-
tubStatusModule> for more information on how to compile and configure nginx
and this module.

The following options are accepted by the "nginx plugin":

URL http://host/nginx_status
Sets the URL of the "ngx_http_stub_status_module" output.

User Username
Optional user name needed for authentication.

Password Password
Optional password needed for authentication.

VerifyPeer true|false
Enable or disable peer SSL certificate verification. See
<http://curl.haxx.se/docs/sslcerts.html> for details. Enabled by de-
fault.

Timeout Milliseconds
The Timeout option sets the overall timeout for HTTP requests to URL,
in milliseconds. By default, the configured Interval is used to set the
timeout.

Plugin "notify_desktop"
This plugin sends a desktop notification to a notification daemon, as de-
fined in the Desktop Notification Specification. To actually display the
notifications, notification-daemon is required and collectd has to be able
to access the X server (i. e., the "DISPLAY" and "XAUTHORITY" environment
variables have to be set correctly) and the D-Bus message bus.

The Desktop Notification Specification can be found at
<http://www.galago-project.org/specs/notification/>.

OkayTimeout timeout
WarningTimeout timeout
FailureTimeout timeout
Set the timeout, in milliseconds, after which to expire the notifica-
tion for "OKAY", "WARNING" and "FAILURE" severities respectively. If
zero has been specified, the displayed notification will not be closed
at all - the user has to do so herself. These options default to 5000.
If a negative number has been specified, the default is used as well.

Plugin "notify_email"
The notify_email plugin uses the ESMTP library to send notifications to a
configured email address.

libESMTP is available from <http://www.stafford.uklinux.net/libesmtp/>.

Available configuration options:

From Address
Email address from which the emails should appear to come from.

Default: "root@localhost"

Recipient Address
Configures the email address(es) to which the notifications should be
mailed. May be repeated to send notifications to multiple addresses.

At least one Recipient must be present for the plugin to work cor-
rectly.

SMTPServer Hostname
Hostname of the SMTP server to connect to.

Default: "localhost"

SMTPPort Port
TCP port to connect to.

Default: 25

SMTPUser Username
Username for ASMTP authentication. Optional.

SMTPPassword Password
Password for ASMTP authentication. Optional.

Subject Subject
Subject-template to use when sending emails. There must be exactly two
string-placeholders in the subject, given in the standard printf(3)
syntax, i. e. %s. The first will be replaced with the severity, the
second with the hostname.

Default: "Collectd notify: %s@%s"

Plugin "notify_nagios"
The notify_nagios plugin writes notifications to Nagios' command file as a
passive service check result.

Available configuration options:

CommandFile Path
Sets the command file to write to. Defaults to /usr/local/na-
gios/var/rw/nagios.cmd.

Plugin "ntpd"
The "ntpd" plugin collects per-peer ntp data such as time offset and time
dispersion.

For talking to ntpd, it mimics what the ntpdc control program does on the
wire - using mode 7 specific requests. This mode is deprecated with newer
ntpd releases (4.2.7p230 and later). For the "ntpd" plugin to work cor-
rectly with them, the ntp daemon must be explicitly configured to enable
mode 7 (which is disabled by default). Refer to the ntp.conf(5) manual page
for details.

Available configuration options for the "ntpd" plugin:

Host Hostname
Hostname of the host running ntpd. Defaults to localhost.

Port Port
UDP-Port to connect to. Defaults to 123.

ReverseLookups true|false
Sets whether or not to perform reverse lookups on peers. Since the name
or IP-address may be used in a filename it is recommended to disable
reverse lookups. The default is to do reverse lookups to preserve back-
wards compatibility, though.

IncludeUnitID true|false
When a peer is a refclock, include the unit ID in the type instance.
Defaults to false for backward compatibility.

If two refclock peers use the same driver and this is false, the plugin
will try to write simultaneous measurements from both to the same type
instance. This will result in error messages in the log and only one
set of measurements making it through.

Plugin "nut"
UPS upsname@hostname[:port]
Add a UPS to collect data from. The format is identical to the one ac-
cepted by upsc(8).

ForceSSL true|false
Stops connections from falling back to unsecured if an SSL connection
cannot be established. Defaults to false if undeclared.

VerifyPeer true|false
If set to true, requires a CAPath be provided. Will use the CAPath to
find certificates to use as Trusted Certificates to validate a upsd
server certificate. If validation of the upsd server certificate
fails, the connection will not be established. If ForceSSL is unde-
clared or set to false, setting VerifyPeer to true will override and
set ForceSSL to true.

CAPath I/path/to/certs/folder
If VerifyPeer is set to true, this is required. Otherwise this is ig-
nored. The folder pointed at must contain certificate(s) named accord-
ing to their hash. Ex: XXXXXXXX.Y where X is the hash value of a cert
and Y is 0. If name collisions occur because two different certs have
the same hash value, Y can be incremented in order to avoid conflict.
To create a symbolic link to a certificate the following command can be
used from within the directory where the cert resides:

"ln -s some.crt ./$(openssl x509 -hash -noout -in some.crt).0"

Alternatively, the package openssl-perl provides a command "c_rehash"
that will generate links like the one described above for ALL certs in
a given folder. Example usage: "c_rehash /path/to/certs/folder"

ConnectTimeout Milliseconds
The ConnectTimeout option sets the connect timeout, in milliseconds.
By default, the configured Interval is used to set the timeout.

Plugin "olsrd"
The olsrd plugin connects to the TCP port opened by the txtinfo plugin of
the Optimized Link State Routing daemon and reads information about the
current state of the meshed network.

The following configuration options are understood:

Host Host
Connect to Host. Defaults to "localhost".

Port Port
Specifies the port to connect to. This must be a string, even if you
give the port as a number rather than a service name. Defaults to
"2006".

CollectLinks No|Summary|Detail
Specifies what information to collect about links, i. e. direct connec-
tions of the daemon queried. If set to No, no information is collected.
If set to Summary, the number of links and the average of all link
quality (LQ) and neighbor link quality (NLQ) values is calculated. If
set to Detail LQ and NLQ are collected per link.

Defaults to Detail.

CollectRoutes No|Summary|Detail
Specifies what information to collect about routes of the daemon
queried. If set to No, no information is collected. If set to Summary,
the number of routes and the average metric and ETX is calculated. If
set to Detail metric and ETX are collected per route.

Defaults to Summary.

CollectTopology No|Summary|Detail
Specifies what information to collect about the global topology. If set
to No, no information is collected. If set to Summary, the number of
links in the entire topology and the average link quality (LQ) is cal-
culated. If set to Detail LQ and NLQ are collected for each link in
the entire topology.

Defaults to Summary.

Plugin "onewire"
EXPERIMENTAL! See notes below.

The "onewire" plugin uses the owcapi library from the owfs project
<http://owfs.org/> to read sensors connected via the onewire bus.

It can be used in two possible modes - standard or advanced.

In the standard mode only temperature sensors (sensors with the family code
10, 22 and 28 - e.g. DS1820, DS18S20, DS1920) can be read. If you have
other sensors you would like to have included, please send a sort request
to the mailing list. You can select sensors to be read or to be ignored de-
pending on the option IgnoreSelected). When no list is provided the whole
bus is walked and all sensors are read.

Hubs (the DS2409 chips) are working, but read the note, why this plugin is
experimental, below.

In the advanced mode you can configure any sensor to be read (only numeri-
cal value) using full OWFS path (e.g. "/uncached/10.F10FCA000800/tempera-
ture"). In this mode you have to list all the sensors. Neither default bus
walk nor IgnoreSelected are used here. Address and type (file) is extracted
from the path automatically and should produce compatible structure with
the "standard" mode (basically the path is expected as for example "/un-
cached/10.F10FCA000800/temperature" where it would extract address part
"F10FCA000800" and the rest after the slash is considered the type - here
"temperature"). There are two advantages to this mode - you can access
virtually any sensor (not just temperature), select whether to use cached
or directly read values and it is slighlty faster. The downside is more
complex configuration.

The two modes are distinguished automatically by the format of the address.
It is not possible to mix the two modes. Once a full path is detected in
any Sensor then the whole addressing (all sensors) is considered to be this
way (and as standard addresses will fail parsing they will be ignored).

Device Device
Sets the device to read the values from. This can either be a "real"
hardware device, such as a serial port or an USB port, or the address
of the owserver(1) socket, usually localhost:4304.

Though the documentation claims to automatically recognize the given
address format, with version 2.7p4 we had to specify the type explic-
itly. So with that version, the following configuration worked for us:

<Plugin onewire>
Device "-s localhost:4304"
</Plugin>

This directive is required and does not have a default value.

Sensor Sensor
In the standard mode selects sensors to collect or to ignore (depending
on IgnoreSelected, see below). Sensors are specified without the family
byte at the beginning, so you have to use for example "F10FCA000800",
and not include the leading 10. family byte and point. When no Sensor
is configured the whole Onewire bus is walked and all supported sensors
(see above) are read.

In the advanced mode the Sensor specifies full OWFS path - e.g. "/un-
cached/10.F10FCA000800/temperature" (or when cached values are OK
"/10.F10FCA000800/temperature"). IgnoreSelected is not used.

As there can be multiple devices on the bus you can list multiple sen-
sor (use multiple Sensor elements).

See /"IGNORELISTS" for details.

IgnoreSelected true|false
If no configuration is given, the onewire plugin will collect data from
all sensors found. This may not be practical, especially if sensors are
added and removed regularly. Sometimes, however, it's easier/preferred
to collect only specific sensors or all sensors except a few specified
ones. This option enables you to do that: By setting IgnoreSelected to
true the effect of Sensor is inverted: All selected interfaces are ig-
nored and all other interfaces are collected.

Used only in the standard mode - see above.

Interval Seconds
Sets the interval in which all sensors should be read. If not speci-
fied, the global Interval setting is used.

EXPERIMENTAL! The "onewire" plugin is experimental, because it doesn't yet
work with big setups. It works with one sensor being attached to one con-
troller, but as soon as you throw in a couple more senors and maybe a hub
or two, reading all values will take more than ten seconds (the default in-
terval). We will probably add some separate thread for reading the sensors
and some cache or something like that, but it's not done yet. We will try
to maintain backwards compatibility in the future, but we can't promise. So
in short: If it works for you: Great! But keep in mind that the config
might change, though this is unlikely. Oh, and if you want to help improv-
ing this plugin, just send a short notice to the mailing list. Thanks :)

Plugin "openldap"
To use the "openldap" plugin you first need to configure the OpenLDAP
server correctly. The backend database "monitor" needs to be loaded and
working. See slapd-monitor(5) for the details.

The configuration of the "openldap" plugin consists of one or more Instance
blocks. Each block requires one string argument as the instance name. For
example:

<Plugin "openldap">
<Instance "foo">
URL "ldap://localhost/"
</Instance>
<Instance "bar">
URL "ldaps://localhost/"
</Instance>
</Plugin>

The following options are accepted within each Instance block:

URL ldap://host/binddn
Sets the URL to use to connect to the OpenLDAP server. This option is
mandatory.

BindDN BindDN
Name in the form of an LDAP distinguished name intended to be used for
authentication. Defaults to empty string to establish an anonymous au-
thorization.

Password Password
Password for simple bind authentication. If this option is not set,
unauthenticated bind operation is used.

StartTLS true|false
Defines whether TLS must be used when connecting to the OpenLDAP
server. Disabled by default.

VerifyHost true|false
Enables or disables peer host name verification. If enabled, the plugin
checks if the "Common Name" or a "Subject Alternate Name" field of the
SSL certificate matches the host name provided by the URL option. If
this identity check fails, the connection is aborted. Enabled by de-
fault.

CACert File
File that holds one or more SSL certificates. If you want to use
TLS/SSL you may possibly need this option. What CA certificates are
checked by default depends on the distribution you use and can be
changed with the usual ldap client configuration mechanisms. See
ldap.conf(5) for the details.

Timeout Seconds
Sets the timeout value for ldap operations, in seconds. By default, the
configured Interval is used to set the timeout. Use -1 to disable (in-
finite timeout).

Version Version
An integer which sets the LDAP protocol version number to use when con-
necting to the OpenLDAP server. Defaults to 3 for using LDAPv3.

Plugin "openvpn"
The OpenVPN plugin reads a status file maintained by OpenVPN and gathers
traffic statistics about connected clients.

To set up OpenVPN to write to the status file periodically, use the --sta-
tus option of OpenVPN.

So, in a nutshell you need:

openvpn $OTHER_OPTIONS \
--status "/var/run/openvpn-status" 10

Available options:

StatusFile File
Specifies the location of the status file.

ImprovedNamingSchema true|false
When enabled, the filename of the status file will be used as plugin
instance and the client's "common name" will be used as type instance.
This is required when reading multiple status files. Enabling this op-
tion is recommended, but to maintain backwards compatibility this op-
tion is disabled by default.

CollectCompression true|false
Sets whether or not statistics about the compression used by OpenVPN
should be collected. This information is only available in single mode.
Enabled by default.

CollectIndividualUsers true|false
Sets whether or not traffic information is collected for each connected
client individually. If set to false, currently no traffic data is col-
lected at all because aggregating this data in a save manner is tricky.
Defaults to true.

CollectUserCount true|false
When enabled, the number of currently connected clients or users is
collected. This is especially interesting when CollectIndividualUsers
is disabled, but can be configured independently from that option. De-
faults to false.

Plugin "oracle"
The "oracle" plugin uses the OracleA(R) Call Interface (OCI) to connect to
an OracleA(R) Database and lets you execute SQL statements there. It is
very similar to the "dbi" plugin, because it was written around the same
time. See the "dbi" plugin's documentation above for details.

<Plugin oracle>
<Query "out_of_stock">
Statement "SELECT category, COUNT(*) AS value FROM products WHERE in_stock = 0 GROUP BY category"
<Result>
Type "gauge"
# InstancePrefix "foo"
InstancesFrom "category"
ValuesFrom "value"
</Result>
</Query>
<Database "product_information">
#Plugin "warehouse"
ConnectID "db01"
Username "oracle"
Password "secret"
Query "out_of_stock"
</Database>
</Plugin>

Query blocks

The Query blocks are handled identically to the Query blocks of the "dbi"
plugin. Please see its documentation above for details on how to specify
queries.

Database blocks

Database blocks define a connection to a database and which queries should
be sent to that database. Each database needs a "name" as string argument
in the starting tag of the block. This name will be used as "PluginIn-
stance" in the values submitted to the daemon. Other than that, that name
is not used.

Plugin Plugin
Use Plugin as the plugin name when submitting query results from this
Database. Defaults to "oracle".

ConnectID ID
Defines the "database alias" or "service name" to connect to. Usually,
these names are defined in the file named "$ORACLE_HOME/network/ad-
min/tnsnames.ora".

Host Host
Hostname to use when dispatching values for this database. Defaults to
using the global hostname of the collectd instance.

Username Username
Username used for authentication.

Password Password
Password used for authentication.

Plugin "ovs_events"
The ovs_events plugin monitors the link status of Open vSwitch (OVS) con-
nected interfaces, dispatches the values to collectd and sends the notifi-
cation whenever the link state change occurs. This plugin uses OVS database
to get a link state change notification.

Synopsis:

<Plugin "ovs_events">
Port 6640
Address "127.0.0.1"
Socket "/var/run/openvswitch/db.sock"
Interfaces "br0" "veth0"
SendNotification true
DispatchValues false
</Plugin>

The plugin provides the following configuration options:

Address node
The address of the OVS DB server JSON-RPC interface used by the plugin.
To enable the interface, OVS DB daemon should be running with "--re-
mote=ptcp:" option. See ovsdb-server(1) for more details. The option
may be either network hostname, IPv4 numbers-and-dots notation or IPv6
hexadecimal string format. Defaults to "localhost".

Port service
TCP-port to connect to. Either a service name or a port number may be
given. Defaults to 6640.

Socket path
The UNIX domain socket path of OVS DB server JSON-RPC interface used by
the plugin. To enable the interface, the OVS DB daemon should be run-
ning with "--remote=punix:" option. See ovsdb-server(1) for more de-
tails. If this option is set, Address and Port options are ignored.

Interfaces [ifname ...]
List of interface names to be monitored by this plugin. If this option
is not specified or is empty then all OVS connected interfaces on all
bridges are monitored.

Default: empty (all interfaces on all bridges are monitored)

SendNotification true|false
If set to true, OVS link notifications (interface status and OVS DB
connection terminate) are sent to collectd. Default value is true.

DispatchValues true|false
Dispatch the OVS DB interface link status value with configured plugin
interval. Defaults to false. Please note, if SendNotification and Dis-
patchValues options are false, no OVS information will be provided by
the plugin.

Note: By default, the global interval setting is used within which to re-
trieve the OVS link status. To configure a plugin-specific interval, please
use Interval option of the OVS LoadPlugin block settings. For milliseconds
simple divide the time by 1000 for example if the desired interval is 50ms,
set interval to 0.05.

Plugin "ovs_stats"
The ovs_stats plugin collects statistics of OVS connected interfaces. This
plugin uses OVSDB management protocol (RFC7047) monitor mechanism to get
statistics from OVSDB

Synopsis:

<Plugin "ovs_stats">
Port 6640
Address "127.0.0.1"
Socket "/var/run/openvswitch/db.sock"
Bridges "br0" "br_ext"
InterfaceStats false
</Plugin>

The plugin provides the following configuration options:

Port service
TCP-port to connect to. Either a service name or a port number may be
given. Defaults to 6640.

Bridges [brname ...]
List of OVS bridge names to be monitored by this plugin. If this option
is omitted or is empty then all OVS bridges will be monitored.

Default: empty (monitor all bridges)

InterfaceStats false|true
Indicates that the plugin should gather statistics for individual in-
terfaces in addition to ports. This can be useful when monitoring an
OVS setup with bond ports, where you might wish to know individual sta-
tistics for the interfaces included in the bonds. Defaults to false.

Plugin "pcie_errors"
The pcie_errors plugin collects PCI Express errors from Device Status in
Capability structure and from Advanced Error Reporting Extended Capability
where available. At every read it polls config space of PCI Express de-
vices and dispatches notification for every error that is set. It checks
for new errors at every read. The device is indicated in plugin_instance
according to format "domain:bus:dev.fn". Errors are divided into cate-
gories indicated by type_instance: "correctable", and for uncorrectable er-
rors "non_fatal" or "fatal". Fatal errors are reported as NOTIF_FAILURE
and all others as NOTIF_WARNING.

Synopsis:

<Plugin "pcie_errors">
Source "sysfs"
AccessDir "/sys/bus/pci"
ReportMasked false
PersistentNotifications false
</Plugin>

Options:

Source sysfs|proc
Use sysfs or proc to read data from /sysfs or /proc. The default value
is sysfs.

AccessDir dir
Directory used to access device config space. It is optional and de-
faults to /sys/bus/pci for sysfs and to /proc/bus/pci for proc.

ReportMasked false|true
If true plugin will notify about errors that are set to masked in Error
Mask register. Such errors are not reported to the PCI Express Root
Complex. Defaults to false.

PersistentNotifications false|true
If false plugin will dispatch notification only on set/clear of error.
The ones already reported will be ignored. Defaults to false.

Plugin "perl"
This plugin embeds a Perl-interpreter into collectd and provides an inter-
face to collectd's plugin system. See collectd-perl(5) for its documenta-
tion.

Plugin "pinba"
The Pinba plugin receives profiling information from Pinba, an extension
for the PHP interpreter. At the end of executing a script, i.e. after a
PHP-based webpage has been delivered, the extension will send a UDP packet
containing timing information, peak memory usage and so on. The plugin will
wait for such packets, parse them and account the provided information,
which is then dispatched to the daemon once per interval.

Synopsis:

<Plugin pinba>
Address "::0"
Port "30002"
# Overall statistics for the website.
<View "www-total">
Server "www.example.com"
</View>
# Statistics for www-a only
<View "www-a">
Host "www-a.example.com"
Server "www.example.com"
</View>
# Statistics for www-b only
<View "www-b">
Host "www-b.example.com"
Server "www.example.com"
</View>
</Plugin>

The plugin provides the following configuration options:

Address Node
Configures the address used to open a listening socket. By default,
plugin will bind to the any address "::0".

Port Service
Configures the port (service) to bind to. By default the default Pinba
port "30002" will be used. The option accepts service names in addition
to port numbers and thus requires a string argument.

<View Name> block
The packets sent by the Pinba extension include the hostname of the
server, the server name (the name of the virtual host) and the script
that was executed. Using View blocks it is possible to separate the
data into multiple groups to get more meaningful statistics. Each
packet is added to all matching groups, so that a packet may be ac-
counted for more than once.

Host Host
Matches the hostname of the system the webserver / script is run-
ning on. This will contain the result of the gethostname(2) system
call. If not configured, all hostnames will be accepted.

Server Server
Matches the name of the virtual host, i.e. the contents of the
$_SERVER["SERVER_NAME"] variable when within PHP. If not config-
ured, all server names will be accepted.

Script Script
Matches the name of the script name, i.e. the contents of the
$_SERVER["SCRIPT_NAME"] variable when within PHP. If not config-
ured, all script names will be accepted.

Plugin "ping"
The Ping plugin starts a new thread which sends ICMP "ping" packets to the
configured hosts periodically and measures the network latency. Whenever
the "read" function of the plugin is called, it submits the average la-
tency, the standard deviation and the drop rate for each host.

Available configuration options:

Host IP-address
Host to ping periodically. This option may be repeated several times to
ping multiple hosts.

Interval Seconds
Sets the interval in which to send ICMP echo packets to the configured
hosts. This is not the interval in which metrics are read from the
plugin but the interval in which the hosts are "pinged". Therefore, the
setting here should be smaller than or equal to the global Interval
setting. Fractional times, such as "1.24" are allowed.

Default: 1.0

Timeout Seconds
Time to wait for a response from the host to which an ICMP packet had
been sent. If a reply was not received after Seconds seconds, the host
is assumed to be down or the packet to be dropped. This setting must be
smaller than the Interval setting above for the plugin to work cor-
rectly. Fractional arguments are accepted.

Default: 0.9

TTL 0-255
Sets the Time-To-Live of generated ICMP packets.

Size size
Sets the size of the data payload in ICMP packet to specified size (it
will be filled with regular ASCII pattern). If not set, default 56 byte
long string is used so that the packet size of an ICMPv4 packet is ex-
actly 64 bytes, similar to the behaviour of normal ping(1) command.

SourceAddress host
Sets the source address to use. host may either be a numerical network
address or a network hostname.

AddressFamily af
Sets the address family to use. af may be "any", "ipv4" or "ipv6". This
option will be ignored if you set a SourceAddress.

Device name
Sets the outgoing network device to be used. name has to specify an in-
terface name (e. g. "eth0"). This might not be supported by all operat-
ing systems.

MaxMissed Packets
Trigger a DNS resolve after the host has not replied to Packets pack-
ets. This enables the use of dynamic DNS services (like dyndns.org)
with the ping plugin.

Default: -1 (disabled)

Plugin "postgresql"
The "postgresql" plugin queries statistics from PostgreSQL databases. It
keeps a persistent connection to all configured databases and tries to re-
connect if the connection has been interrupted. A database is configured by
specifying a Database block as described below. The default statistics are
collected from PostgreSQL's statistics collector which thus has to be en-
abled for this plugin to work correctly. This should usually be the case by
default. See the section "The Statistics Collector" of the PostgreSQL Docu-
mentation for details.

By specifying custom database queries using a Query block as described be-
low, you may collect any data that is available from some PostgreSQL data-
base. This way, you are able to access statistics of external daemons which
are available in a PostgreSQL database or use future or special statistics
provided by PostgreSQL without the need to upgrade your collectd installa-
tion.

Starting with version 5.2, the "postgresql" plugin supports writing data to
PostgreSQL databases as well. This has been implemented in a generic way.
You need to specify an SQL statement which will then be executed by col-
lectd in order to write the data (see below for details). The benefit of
that approach is that there is no fixed database layout. Rather, the layout
may be optimized for the current setup.

The PostgreSQL Documentation manual can be found at <http://www.post-
gresql.org/docs/manuals/>.

<Plugin postgresql>
<Query magic>
Statement "SELECT magic FROM wizard WHERE host = $1;"
Param hostname
<Result>
Type gauge
InstancePrefix "magic"
ValuesFrom magic
</Result>
</Query>

<Query rt36_tickets>
Statement "SELECT COUNT(type) AS count, type \
FROM (SELECT CASE \
WHEN resolved = 'epoch' THEN 'open' \
ELSE 'resolved' END AS type \
FROM tickets) type \
GROUP BY type;"
<Result>
Type counter
InstancePrefix "rt36_tickets"
InstancesFrom "type"
ValuesFrom "count"
</Result>
</Query>

<Writer sqlstore>
Statement "SELECT collectd_insert($1, $2, $3, $4, $5, $6, $7, $8, $9);"
StoreRates true
</Writer>

<Database foo>
Plugin "kingdom"
Host "hostname"
Port "5432"
User "username"
Password "secret"
SSLMode "prefer"
KRBSrvName "kerberos_service_name"
Query magic
</Database>

<Database bar>
Interval 300
Service "service_name"
Query backends # predefined
Query rt36_tickets
</Database>

<Database qux>
# ...
Writer sqlstore
CommitInterval 10
</Database>
</Plugin>

The Query block defines one database query which may later be used by a
database definition. It accepts a single mandatory argument which specifies
the name of the query. The names of all queries have to be unique (see the
MinVersion and MaxVersion options below for an exception to this rule).

In each Query block, there is one or more Result blocks. Multiple Result
blocks may be used to extract multiple values from a single query.

The following configuration options are available to define the query:

Statement sql query statement
Specify the sql query statement which the plugin should execute. The
string may contain the tokens $1, $2, etc. which are used to reference
the first, second, etc. parameter. The value of the parameters is spec-
ified by the Param configuration option - see below for details. To in-
clude a literal $ character followed by a number, surround it with sin-
gle quotes (').

Any SQL command which may return data (such as "SELECT" or "SHOW") is
allowed. Note, however, that only a single command may be used. Semi-
colons are allowed as long as a single non-empty command has been spec-
ified only.

The returned lines will be handled separately one after another.

Param hostname|database|instance|username|interval
Specify the parameters which should be passed to the SQL query. The pa-
rameters are referred to in the SQL query as $1, $2, etc. in the same
order as they appear in the configuration file. The value of the para-
meter is determined depending on the value of the Param option as fol-
lows:

hostname
The configured hostname of the database connection. If a UNIX do-
main socket is used, the parameter expands to "localhost".

database
The name of the database of the current connection.

instance
The name of the database plugin instance. See the Instance option
of the database specification below for details.

username
The username used to connect to the database.

interval
The interval with which this database is queried (as specified by
the database specific or global Interval options).

Please note that parameters are only supported by PostgreSQL's protocol
version 3 and above which was introduced in version 7.4 of PostgreSQL.

PluginInstanceFrom column
Specify how to create the "PluginInstance" for reporting this query re-
sults. Only one column is supported. You may concatenate fields and
string values in the query statement to get the required results.

MinVersion version
MaxVersion version
Specify the minimum or maximum version of PostgreSQL that this query
should be used with. Some statistics might only be available with cer-
tain versions of PostgreSQL. This allows you to specify multiple
queries with the same name but which apply to different versions, thus
allowing you to use the same configuration in a heterogeneous environ-
ment.

The version has to be specified as the concatenation of the major, mi-
nor and patch-level versions, each represented as two-decimal-digit
numbers. For example, version 8.2.3 will become 80203.

The Result block defines how to handle the values returned from the query.
It defines which column holds which value and how to dispatch that value to
the daemon.

Type type
The type name to be used when dispatching the values. The type de-
scribes how to handle the data and where to store it. See types.db(5)
for more details on types and their configuration. The number and type
of values (as selected by the ValuesFrom option) has to match the type
of the given name.

This option is mandatory.

InstancePrefix prefix
InstancesFrom column0 [column1 ...]
Specify how to create the "TypeInstance" for each data set (i. e.
line). InstancePrefix defines a static prefix that will be prepended
to all type instances. InstancesFrom defines the column names whose
values will be used to create the type instance. Multiple values will
be joined together using the hyphen ("-") as separation character.

The plugin itself does not check whether or not all built instances are
different. It is your responsibility to assure that each is unique.

Both options are optional. If none is specified, the type instance will
be empty.

ValuesFrom column0 [column1 ...]
Names the columns whose content is used as the actual data for the data
sets that are dispatched to the daemon. How many such columns you need
is determined by the Type setting as explained above. If you specify
too many or not enough columns, the plugin will complain about that and
no data will be submitted to the daemon.

The actual data type, as seen by PostgreSQL, is not that important as
long as it represents numbers. The plugin will automatically cast the
values to the right type if it know how to do that. For that, it uses
the strtoll(3) and strtod(3) functions, so anything supported by those
functions is supported by the plugin as well.

This option is required inside a Result block and may be specified mul-
tiple times. If multiple ValuesFrom options are specified, the columns
are read in the given order.

The following predefined queries are available (the definitions can be
found in the postgresql_default.conf file which, by default, is available
at "prefix/share/collectd/"):

backends
This query collects the number of backends, i. e. the number of con-
nected clients.

transactions
This query collects the numbers of committed and rolled-back transac-
tions of the user tables.

queries
This query collects the numbers of various table modifications (i. e.
insertions, updates, deletions) of the user tables.

query_plans
This query collects the numbers of various table scans and returned tu-
ples of the user tables.

table_states
This query collects the numbers of live and dead rows in the user ta-
bles.

disk_io
This query collects disk block access counts for user tables.

disk_usage
This query collects the on-disk size of the database in bytes.

In addition, the following detailed queries are available by default.
Please note that each of those queries collects information by table, thus,
potentially producing a lot of data. For details see the description of the
non-by_table queries above.

queries_by_table
query_plans_by_table
table_states_by_table
disk_io_by_table

The Writer block defines a PostgreSQL writer backend. It accepts a single
mandatory argument specifying the name of the writer. This will then be
used in the Database specification in order to activate the writer in-
stance. The names of all writers have to be unique. The following options
may be specified:

Statement sql statement
This mandatory option specifies the SQL statement that will be executed
for each submitted value. A single SQL statement is allowed only. Any-
thing after the first semicolon will be ignored.

Nine parameters will be passed to the statement and should be specified
as tokens $1, $2, through $9 in the statement string. The following
values are made available through those parameters:

$1 The timestamp of the queried value as an RFC 3339-formatted local
time.

$2 The hostname of the queried value.

$3 The plugin name of the queried value.

$4 The plugin instance of the queried value. This value may be NULL if
there is no plugin instance.

$5 The type of the queried value (cf. types.db(5)).

$6 The type instance of the queried value. This value may be NULL if
there is no type instance.

$7 An array of names for the submitted values (i. e., the name of the
data sources of the submitted value-list).

$8 An array of types for the submitted values (i. e., the type of the
data sources of the submitted value-list; "counter", "gauge", ...).
Note, that if StoreRates is enabled (which is the default, see be-
low), all types will be "gauge".

$9 An array of the submitted values. The dimensions of the value name
and value arrays match.

In general, it is advisable to create and call a custom function in the
PostgreSQL database for this purpose. Any procedural language supported
by PostgreSQL will do (see chapter "Server Programming" in the Post-
greSQL manual for details).

StoreRates false|true
If set to true (the default), convert counter values to rates. If set
to false counter values are stored as is, i. e. as an increasing inte-
ger number.

The Database block defines one PostgreSQL database for which to collect
statistics. It accepts a single mandatory argument which specifies the
database name. None of the other options are required. PostgreSQL will use
default values as documented in the section "CONNECTING TO A DATABASE" in
the psql(1) manpage. However, be aware that those defaults may be influ-
enced by the user collectd is run as and special environment variables. See
the manpage for details.

Interval seconds
Specify the interval with which the database should be queried. The de-
fault is to use the global Interval setting.

CommitInterval seconds
This option may be used for database connections which have "writers"
assigned (see above). If specified, it causes a writer to put several
updates into a single transaction. This transaction will last for the
specified amount of time. By default, each update will be executed in a
separate transaction. Each transaction generates a fair amount of over-
head which can, thus, be reduced by activating this option. The
draw-back is, that data covering the specified amount of time will be
lost, for example, if a single statement within the transaction fails
or if the database server crashes.

Plugin Plugin
Use Plugin as the plugin name when submitting query results from this
Database. Defaults to "postgresql".

Instance name
Specify the plugin instance name that should be used instead of the
database name (which is the default, if this option has not been speci-
fied). This allows one to query multiple databases of the same name on
the same host (e.g. when running multiple database server versions in
parallel). The plugin instance name can also be set from the query re-
sult using the PluginInstanceFrom option in Query block.

Host hostname
Specify the hostname or IP of the PostgreSQL server to connect to. If
the value begins with a slash, it is interpreted as the directory name
in which to look for the UNIX domain socket.

This option is also used to determine the hostname that is associated
with a collected data set. If it has been omitted or either begins with
with a slash or equals localhost it will be replaced with the global
hostname definition of collectd. Any other value will be passed liter-
ally to collectd when dispatching values. Also see the global Hostname
and FQDNLookup options.

Port port
Specify the TCP port or the local UNIX domain socket file extension of
the server.

User username
Specify the username to be used when connecting to the server.

Password password
Specify the password to be used when connecting to the server.

ExpireDelay delay
Skip expired values in query output.

SSLMode disable|allow|prefer|require
Specify whether to use an SSL connection when contacting the server.
The following modes are supported:

disable
Do not use SSL at all.

allow
First, try to connect without using SSL. If that fails, try using
SSL.

prefer (default)
First, try to connect using SSL. If that fails, try without using
SSL.

require
Use SSL only.

KRBSrvName kerberos_service_name
Specify the Kerberos service name to use when authenticating with Ker-
beros 5 or GSSAPI. See the sections "Kerberos authentication" and "GSS-
API" of the PostgreSQL Documentation for details.

Service service_name
Specify the PostgreSQL service name to use for additional parameters.
That service has to be defined in pg_service.conf and holds additional
connection parameters. See the section "The Connection Service File" in
the PostgreSQL Documentation for details.

Query query
Specifies a query which should be executed in the context of the data-
base connection. This may be any of the predefined or user-defined
queries. If no such option is given, it defaults to "backends", "trans-
actions", "queries", "query_plans", "table_states", "disk_io" and
"disk_usage" (unless a Writer has been specified). Else, the specified
queries are used only.

Writer writer
Assigns the specified writer backend to the database connection. This
causes all collected data to be send to the database using the settings
defined in the writer configuration (see the section "FILTER CONFIGURA-
TION" below for details on how to selectively send data to certain plu-
gins).

Each writer will register a flush callback which may be used when hav-
ing long transactions enabled (see the CommitInterval option above).
When issuing the FLUSH command (see collectd-unixsock(5) for details)
the current transaction will be committed right away. Two different
kinds of flush callbacks are available with the "postgresql" plugin:

postgresql
Flush all writer backends.

postgresql-database
Flush all writers of the specified database only.

Plugin "powerdns"
The "powerdns" plugin queries statistics from an authoritative PowerDNS
nameserver and/or a PowerDNS recursor. Since both offer a wide variety of
values, many of which are probably meaningless to most users, but may be
useful for some. So you may chose which values to collect, but if you
don't, some reasonable defaults will be collected.

<Plugin "powerdns">
<Server "server_name">
Collect "latency"
Collect "udp-answers" "udp-queries"
Socket "/var/run/pdns.controlsocket"
</Server>
<Recursor "recursor_name">
Collect "questions"
Collect "cache-hits" "cache-misses"
Socket "/var/run/pdns_recursor.controlsocket"
</Recursor>
LocalSocket "/opt/collectd/var/run/collectd-powerdns"
</Plugin>

Server and Recursor block
The Server block defines one authoritative server to query, the Recur-
sor does the same for an recursing server. The possible options in both
blocks are the same, though. The argument defines a name for the
server / recursor and is required.

Collect Field
Using the Collect statement you can select which values to collect.
Here, you specify the name of the values as used by the PowerDNS
servers, e. g. "dlg-only-drops", "answers10-100".

The method of getting the values differs for Server and Recursor
blocks: When querying the server a "SHOW *" command is issued in
any case, because that's the only way of getting multiple values
out of the server at once. collectd then picks out the values you
have selected. When querying the recursor, a command is generated
to query exactly these values. So if you specify invalid fields
when querying the recursor, a syntax error may be returned by the
daemon and collectd may not collect any values at all.

If no Collect statement is given, the following Server values will
be collected:

latency
packetcache-hit
packetcache-miss
packetcache-size
query-cache-hit
query-cache-miss
recursing-answers
recursing-questions
tcp-answers
tcp-queries
udp-answers
udp-queries

The following Recursor values will be collected by default:

noerror-answers
nxdomain-answers
servfail-answers
sys-msec
user-msec
qa-latency
cache-entries
cache-hits
cache-misses
questions

Please note that up to that point collectd doesn't know what values
are available on the server and values that are added do not need a
change of the mechanism so far. However, the values must be mapped
to collectd's naming scheme, which is done using a lookup table
that lists all known values. If values are added in the future and
collectd does not know about them, you will get an error much like
this:

powerdns plugin: submit: Not found in lookup table: foobar = 42

In this case please file a bug report with the collectd team.

Socket Path
Configures the path to the UNIX domain socket to be used when con-
necting to the daemon. By default "${localstatedir}/run/pdns.con-
trolsocket" will be used for an authoritative server and "${local-
statedir}/run/pdns_recursor.controlsocket" will be used for the re-
cursor.

LocalSocket Path
Querying the recursor is done using UDP. When using UDP over UNIX do-
main sockets, the client socket needs a name in the file system, too.
You can set this local name to Path using the LocalSocket option. The
default is "prefix/var/run/collectd-powerdns".

Plugin "processes"
Collects information about processes of local system.

By default, with no process matches configured, only general statistics is
collected: the number of processes in each state and fork rate.

Process matches can be configured by Process and ProcessMatch options.
These may also be a block in which further options may be specified.

The statistics collected for matched processes are:
- size of the resident segment size (RSS)
- user- and system-time used
- number of processes
- number of threads
- number of open files (under Linux)
- number of memory mapped files (under Linux)
- io data (where available)
- context switches (under Linux)
- minor and major pagefaults
- Delay Accounting information (Linux only, requires libmnl)

Synopsis:

<Plugin processes>
CollectFileDescriptor true
CollectContextSwitch true
CollectDelayAccounting false
Process "name"
ProcessMatch "name" "regex"
<Process "collectd">
CollectFileDescriptor false
CollectContextSwitch false
CollectDelayAccounting true
</Process>
<ProcessMatch "name" "regex">
CollectFileDescriptor false
CollectContextSwitch true
</ProcessMatch>
</Plugin>

Process Name
Select more detailed statistics of processes matching this name.

Some platforms have a limit on the length of process names. Name must
stay below this limit.

ProcessMatch name regex
Select more detailed statistics of processes matching the specified
regex (see regex(7) for details). The statistics of all matching
processes are summed up and dispatched to the daemon using the speci-
fied name as an identifier. This allows one to "group" several
processes together. name must not contain slashes.

CollectContextSwitch Boolean
Collect the number of context switches for matched processes. Disabled
by default.

CollectDelayAccounting Boolean
If enabled, collect Linux Delay Accounding information for matching
processes. Delay Accounting provides the time processes wait for the
CPU to become available, for I/O operations to finish, for pages to be
swapped in and for freed pages to be reclaimed. The metrics are re-
ported as "seconds per second" using the "delay_rate" type, e.g. "de-
lay_rate-delay-cpu". Disabled by default.

This option is only available on Linux, requires the "libmnl" library
and requires the "CAP_NET_ADMIN" capability at runtime.

CollectFileDescriptor Boolean
Collect number of file descriptors of matched processes. Disabled by
default.

CollectMemoryMaps Boolean
Collect the number of memory mapped files of the process. The limit
for this number is configured via /proc/sys/vm/max_map_count in the
Linux kernel.

The CollectContextSwitch, CollectDelayAccounting, CollectFileDescriptor and
CollectMemoryMaps options may be used inside Process and ProcessMatch
blocks. When used there, these options affect reporting the corresponding
processes only. Outside of Process and ProcessMatch blocks these options
set the default value for subsequent matches.

Plugin "procevent"
The procevent plugin monitors when processes start (EXEC) and stop (EXIT).

Synopsis:

<Plugin procevent>
BufferLength 10
Process "name"
ProcessRegex "regex"
</Plugin>

Options:

BufferLength length
Maximum number of process events that can be stored in plugin's ring
buffer. By default, this is set to 10. Once an event has been read,
its location becomes available for storing a new event.

Process name
Enumerate a process name to monitor. All processes that match this ex-
act name will be monitored for EXECs and EXITs.

ProcessRegex regex
Enumerate a process pattern to monitor. All processes that match this
regular expression will be monitored for EXECs and EXITs.

Plugin "protocols"
Collects a lot of information about various network protocols, such as IP,
TCP, UDP, etc.

Available configuration options:

Value Selector
Selects whether or not to select a specific value. The string being
matched is of the form "Protocol:ValueName", where Protocol will be
used as the plugin instance and ValueName will be used as type in-
stance. An example of the string being used would be "Tcp:RetransSegs".

You can use regular expressions to match a large number of values with
just one configuration option. To select all "extended" TCP values, you
could use the following statement:

Value "/^TcpExt:/"

Whether only matched values are selected or all matched values are ig-
nored depends on the IgnoreSelected. By default, only matched values
are selected. If no value is configured at all, all values will be se-
lected.

See /"IGNORELISTS" for details.

IgnoreSelected true|false
If set to true, inverts the selection made by Value, i. e. all matching
values will be ignored.

Plugin "python"
This plugin embeds a Python-interpreter into collectd and provides an in-
terface to collectd's plugin system. See collectd-python(5) for its docu-
mentation.

Plugin "redfish"
The "redfish" plugin collects sensor data using REST protocol called Red-
fish.

Sample configuration:

<Plugin redfish>
<Query "fans">
Endpoint "/redfish/v1/Chassis/Chassis-1/Thermal"
<Resource "Fans">
<Property "ReadingRPM">
PluginInstance "chassis-1"
Type "rpm"
</Property>
</Resource>
</Query>
<Query "temperatures">
Endpoint "/redfish/v1/Chassis/Chassis-1/Thermal"
<Resource "Temperatures">
<Property "ReadingCelsius">
PluginInstance "chassis-1"
Type "degrees"
</Property>
</Resource>
</Query>
<Query "voltages">
Endpoint "/redfish/v1/Chassis/Chassis-1/Power"
<Resource "Voltages">
<Property "ReadingVolts">
PluginInstance "chassis-1"
Type "volts"
</Property>
</Resource>
</Query>
<Service "local">
Host "127.0.0.1:5000"
User "user"
Passwd "passwd"
Queries "fans" "voltages" "temperatures"
</Service>
</Plugin>

Query
Section defining a query performed on Redfish interface

Endpoint
URI of the REST API Endpoint for accessing the BMC

Resource
Selects single resource or array to collect data.

Property
Selects property from which data is gathered

PluginInstance
Plugin instance of dispatched collectd metric

TypeType of dispatched collectd metric

TypeInstance
Type instance of collectd metric

Service
Section defining service to be sent requests

Username
BMC username

Password
BMC password

Queries
Queries to run

Plugin "routeros"
The "routeros" plugin connects to a device running RouterOS, the
Linux-based operating system for routers by MikroTik. The plugin uses li-
brouteros to connect and reads information about the interfaces and wire-
less connections of the device. The configuration supports querying multi-
ple routers:

<Plugin "routeros">
<Router>
Host "router0.example.com"
User "collectd"
Password "secr3t"
CollectInterface true
CollectCPULoad true
CollectMemory true
</Router>
<Router>
Host "router1.example.com"
User "collectd"
Password "5ecret"
CollectInterface true
CollectRegistrationTable true
CollectDF true
CollectDisk true
CollectHealth true
</Router>
</Plugin>

As you can see above, the configuration of the routeros plugin consists of
one or more <Router> blocks. Within each block, the following options are
understood:

Host Host
Hostname or IP-address of the router to connect to.

Port Port
Port name or port number used when connecting. If left unspecified, the
default will be chosen by librouteros, currently "8728". This option
expects a string argument, even when a numeric port number is given.

User User
Use the user name User to authenticate. Defaults to "admin".

Password Password
Set the password used to authenticate.

CollectInterface true|false
When set to true, interface statistics will be collected for all inter-
faces present on the device. Defaults to false.

CollectRegistrationTable true|false
When set to true, information about wireless LAN connections will be
collected. Defaults to false.

CollectCPULoad true|false
When set to true, information about the CPU usage will be collected.
The number is a dimensionless value where zero indicates no CPU usage
at all. Defaults to false.

CollectMemory true|false
When enabled, the amount of used and free memory will be collected. How
used memory is calculated is unknown, for example whether or not caches
are counted as used space. Defaults to false.

CollectDF true|false
When enabled, the amount of used and free disk space will be collected.
Defaults to false.

CollectDisk true|false
When enabled, the number of sectors written and bad blocks will be col-
lected. Defaults to false.

CollectHealth true|false
When enabled, the health statistics will be collected. This includes
the voltage and temperature on supported hardware. Defaults to false.

Plugin "redis"
The Redis plugin connects to one or more Redis servers, gathers information
about each server's state and executes user-defined queries. For each
server there is a Node block which configures the connection parameters and
set of user-defined queries for this node.

<Plugin redis>
<Node "example">
Host "localhost"
Port "6379"
#Socket "/var/run/redis/redis.sock"
Timeout 2000
ReportCommandStats false
ReportCpuUsage true
<Query "LLEN myqueue">
#Database 0
Type "queue_length"
Instance "myqueue"
</Query>
</Node>
</Plugin>

Node Nodename
The Node block identifies a new Redis node, that is a new Redis in-
stance running in an specified host and port. The name for node is a
canonical identifier which is used as plugin instance. It is limited to
128 characters in length.

When no Node is configured explicitly, plugin connects to "local-
host:6379".

Host Hostname
The Host option is the hostname or IP-address where the Redis instance
is running on.

Port Port
The Port option is the TCP port on which the Redis instance accepts
connections. Either a service name of a port number may be given.
Please note that numerical port numbers must be given as a string, too.

Socket Path
Connect to Redis using the UNIX domain socket at Path. If this setting
is given, the Hostname and Port settings are ignored.

Password Password
Use Password to authenticate when connecting to Redis.

Timeout Milliseconds
The Timeout option set the socket timeout for node response. Since the
Redis read function is blocking, you should keep this value as low as
possible. It is expected what Timeout values should be lower than In-
terval defined globally.

Defaults to 2000 (2 seconds).

ReportCommandStats false|true
Enables or disables reporting of statistics based on the command type,
including rate of command calls and average CPU time consumed by com-
mand processing. Defaults to false.

ReportCpuUsage true|false
Enables or disables reporting of CPU consumption statistics. Defaults
to true.

Query Querystring
The Query block identifies a query to execute against the redis server.
There may be an arbitrary number of queries to execute. Each query
should return single string or integer.

Type Collectd type
Within a query definition, a valid collectd type to use as when submit-
ting the result of the query. When not supplied, will default to gauge.

Currently only types with one datasource are supported. See
types.db(5) for more details on types and their configuration.

Instance Type instance
Within a query definition, an optional type instance to use when sub-
mitting the result of the query. When not supplied will default to the
escaped command, up to 128 chars.

Database Index
This index selects the Redis logical database to use for query. De-
faults to 0.

Plugin "rrdcached"
The "rrdcached" plugin uses the RRDtool accelerator daemon, rrdcached(1),
to store values to RRD files in an efficient manner. The combination of the
"rrdcached" plugin and the "rrdcached" daemon is very similar to the way
the "rrdtool" plugin works (see below). The added abstraction layer pro-
vides a number of benefits, though: Because the cache is not within "col-
lectd" anymore, it does not need to be flushed when "collectd" is to be
restarted. This results in much shorter (if any) gaps in graphs, especially
under heavy load. Also, the "rrdtool" command line utility is aware of the
daemon so that it can flush values to disk automatically when needed. This
allows one to integrate automated flushing of values into graphing solu-
tions much more easily.

There are disadvantages, though: The daemon may reside on a different host,
so it may not be possible for "collectd" to create the appropriate RRD
files anymore. And even if "rrdcached" runs on the same host, it may run in
a different base directory, so relative paths may do weird stuff if you're
not careful.

So the recommended configuration is to let "collectd" and "rrdcached" run
on the same host, communicating via a UNIX domain socket. The DataDir set-
ting should be set to an absolute path, so that a changed base directory
does not result in RRD files being created / expected in the wrong place.

DaemonAddress Address
Address of the daemon as understood by the "rrdc_connect" function of
the RRD library. See rrdcached(1) for details. Example:

<Plugin "rrdcached">
DaemonAddress "unix:/var/run/rrdcached.sock"
</Plugin>

DataDir Directory
Set the base directory in which the RRD files reside. If this is a rel-
ative path, it is relative to the working base directory of the "rrd-
cached" daemon! Use of an absolute path is recommended.

CreateFiles true|false
Enables or disables the creation of RRD files. If the daemon is not
running locally, or DataDir is set to a relative path, this will not
work as expected. Default is true.

CreateFilesAsync false|true
When enabled, new RRD files are enabled asynchronously, using a sepa-
rate thread that runs in the background. This prevents writes to block,
which is a problem especially when many hundreds of files need to be
created at once. However, since the purpose of creating the files asyn-
chronously is not to block until the file is available, values before
the file is available will be discarded. When disabled (the default)
files are created synchronously, blocking for a short while, while the
file is being written.

StepSize Seconds
Force the stepsize of newly created RRD-files. Ideally (and per de-
fault) this setting is unset and the stepsize is set to the interval in
which the data is collected. Do not use this option unless you ab-
solutely have to for some reason. Setting this option may cause prob-
lems with the "snmp plugin", the "exec plugin" or when the daemon is
set up to receive data from other hosts.

HeartBeat Seconds
Force the heartbeat of newly created RRD-files. This setting should be
unset in which case the heartbeat is set to twice the StepSize which
should equal the interval in which data is collected. Do not set this
option unless you have a very good reason to do so.

RRARows NumRows
The "rrdtool plugin" calculates the number of PDPs per CDP based on the
StepSize, this setting and a timespan. This plugin creates RRD-files
with three times five RRAs, i. e. five RRAs with the CFs MIN, AVERAGE,
and MAX. The five RRAs are optimized for graphs covering one hour, one
day, one week, one month, and one year.

So for each timespan, it calculates how many PDPs need to be consoli-
dated into one CDP by calculating:
number of PDPs = timespan / (stepsize * rrarows)

Bottom line is, set this no smaller than the width of you graphs in
pixels. The default is 1200.

RRATimespan Seconds
Adds an RRA-timespan, given in seconds. Use this option multiple times
to have more then one RRA. If this option is never used, the built-in
default of (3600, 86400, 604800, 2678400, 31622400) is used.

For more information on how RRA-sizes are calculated see RRARows above.

XFF Factor
Set the "XFiles Factor". The default is 0.1. If unsure, don't set this
option. Factor must be in the range "[0.0-1.0)", i.e. between zero
(inclusive) and one (exclusive).

CollectStatistics false|true
When set to true, various statistics about the rrdcached daemon will be
collected, with "rrdcached" as the plugin name. Defaults to false.

Statistics are read via rrdcacheds socket using the STATS command. See
rrdcached(1) for details.

Plugin "rrdtool"
You can use the settings StepSize, HeartBeat, RRARows, and XFF to fine-tune
your RRD-files. Please read rrdcreate(1) if you encounter problems using
these settings. If you don't want to dive into the depths of RRDtool, you
can safely ignore these settings.

DataDir Directory
Set the directory to store RRD files under. By default RRD files are
generated beneath the daemon's working directory, i.e. the BaseDir.

RRARows NumRows
The "rrdtool plugin" calculates the number of PDPs per CDP based on the
StepSize, this setting and a timespan. This plugin creates RRD-files
with three times five RRAs, i.e. five RRAs with the CFs MIN, AVERAGE,
and MAX. The five RRAs are optimized for graphs covering one hour, one
day, one week, one month, and one year.

So for each timespan, it calculates how many PDPs need to be consoli-
dated into one CDP by calculating:
number of PDPs = timespan / (stepsize * rrarows)

Bottom line is, set this no smaller than the width of you graphs in
pixels. The default is 1200.

For more information on how RRA-sizes are calculated see RRARows above.

XFF Factor
Set the "XFiles Factor". The default is 0.1. If unsure, don't set this
option. Factor must be in the range "[0.0-1.0)", i.e. between zero
(inclusive) and one (exclusive).

CacheFlush Seconds
When the "rrdtool" plugin uses a cache (by setting CacheTimeout, see
below) it writes all values for a certain RRD-file if the oldest value
is older than (or equal to) the number of seconds specified by Ca-
cheTimeout. That check happens on new values arriwal. If some RRD-file
is not updated anymore for some reason (the computer was shut down, the
network is broken, etc.) some values may still be in the cache. If
CacheFlush is set, then every Seconds seconds the entire cache is
searched for entries older than CacheTimeout + RandomTimeout seconds.
The entries found are written to disk. Since scanning the entire cache
is kind of expensive and does nothing under normal circumstances, this
value should not be too small. 900 seconds might be a good value,
though setting this to 7200 seconds doesn't normally do much harm ei-
ther.

Defaults to 10x CacheTimeout. CacheFlush must be larger than or equal
to CacheTimeout, otherwise the above default is used.

CacheTimeout Seconds
If this option is set to a value greater than zero, the "rrdtool plu-
gin" will save values in a cache, as described above. Writing multiple
values at once reduces IO-operations and thus lessens the load produced
by updating the files. The trade off is that the graphs kind of "drag
behind" and that more memory is used.

WritesPerSecond Updates
When collecting many statistics with collectd and the "rrdtool" plugin,
you will run serious performance problems. The CacheFlush setting and
the internal update queue assert that collectd continues to work just
fine even under heavy load, but the system may become very unresponsive
and slow. This is a problem especially if you create graphs from the
RRD files on the same machine, for example using the "graph.cgi" script
included in the "contrib/collection3/" directory.

This setting is designed for very large setups. Setting this option to
a value between 25 and 80 updates per second, depending on your hard-
ware, will leave the server responsive enough to draw graphs even while
all the cached values are written to disk. Flushed values, i. e. values
that are forced to disk by the FLUSH command, are not effected by this
limit. They are still written as fast as possible, so that web fron-
tends have up to date data when generating graphs.

For example: If you have 100,000 RRD files and set WritesPerSecond to
30 updates per second, writing all values to disk will take approxi-
mately 56 minutes. Together with the flushing ability that's integrated
into "collection3" you'll end up with a responsive and fast system, up
to date graphs and basically a "backup" of your values every hour.

RandomTimeout Seconds
When set, the actual timeout for each value is chosen randomly between
CacheTimeout-RandomTimeout and CacheTimeout+RandomTimeout. The inten-
tion is to avoid high load situations that appear when many values
timeout at the same time. This is especially a problem shortly after
the daemon starts, because all values were added to the internal cache
at roughly the same time.

Plugin "sensors"
The Sensors plugin uses lm_sensors to retrieve sensor-values. This means
that all the needed modules have to be loaded and lm_sensors has to be con-
figured (most likely by editing /etc/sensors.conf. Read sensors.conf(5) for
details.

The lm_sensors homepage can be found at <http://se-
cure.netroedge.com/~lm78/>.

SensorConfigFile File
Read the lm_sensors configuration from File. When unset (recommended),
the library's default will be used.

Sensor chip-bus-address/type-feature
Selects the name of the sensor which you want to collect or ignore, de-
pending on the IgnoreSelected below. For example, the option "Sensor
it8712-isa-0290/voltage-in1" will cause collectd to gather data for the
voltage sensor in1 of the it8712 on the isa bus at the address 0290.

The value passed to this option has the format "plugin_in-
stance/type-type_instance".

See /"IGNORELISTS" for details.

IgnoreSelected true|false
If no configuration if given, the sensors-plugin will collect data from
all sensors. This may not be practical, especially for uninteresting
sensors. Thus, you can use the Sensor-option to pick the sensors
you're interested in. Sometimes, however, it's easier/preferred to col-
lect all sensors except a few ones. This option enables you to do that:
By setting IgnoreSelected to true the effect of Sensor is inverted: All
selected sensors are ignored and all other sensors are collected.

UseLabels true|false
Configures how sensor readings are reported. When set to true, sensor
readings are reported using their descriptive label (e.g. "VCore").
When set to false (the default) the sensor name is used ("in0").

Plugin "sigrok"
The sigrok plugin uses libsigrok to retrieve measurements from any device
supported by the sigrok <http://sigrok.org/> project.

Synopsis

<Plugin sigrok>
LogLevel 3
<Device "AC Voltage">
Driver "fluke-dmm"
MinimumInterval 10
Conn "/dev/ttyUSB2"
</Device>
<Device "Sound Level">
Driver "cem-dt-885x"
Conn "/dev/ttyUSB1"
</Device>
</Plugin>

LogLevel 0-5
The sigrok logging level to pass on to the collectd log, as a number
between 0 and 5 (inclusive). These levels correspond to "None", "Er-
rors", "Warnings", "Informational", "Debug "and "Spew", respectively.
The default is 2 ("Warnings"). The sigrok log messages, regardless of
their level, are always submitted to collectd at its INFO log level.

<Device Name>
A sigrok-supported device, uniquely identified by this section's op-
tions. The Name is passed to collectd as the plugin instance.

Driver DriverName
The sigrok driver to use for this device.

Conn ConnectionSpec
If the device cannot be auto-discovered, or more than one might be dis-
covered by the driver, ConnectionSpec specifies the connection string
to the device. It can be of the form of a device path
(e.g. "/dev/ttyUSB2"), or, in case of a non-serial USB-connected de-
vice, the USB VendorID.ProductID separated by a period
(e.g. 0403.6001). A USB device can also be specified as Bus.Address
(e.g. 1.41).

SerialComm SerialSpec
For serial devices with non-standard port settings, this option can be
used to specify them in a form understood by sigrok, e.g. "9600/8n1".
This should not be necessary; drivers know how to communicate with de-
vices they support.

MinimumInterval Seconds
Specifies the minimum time between measurement dispatches to collectd,
in seconds. Since some sigrok supported devices can acquire measure-
ments many times per second, it may be necessary to throttle these. For
example, the RRD plugin cannot process writes more than once per sec-
ond.

The default MinimumInterval is 0, meaning measurements received from
the device are always dispatched to collectd. When throttled, unused
measurements are discarded.

Plugin "slurm"
This plugin collects per-partition SLURM node and job state information, as
well as internal health statistics. It takes no options. It should run on
a node that is capable of running the sinfo and squeue commands, i.e. it
has a running slurmd and a valid slurm.conf. Note that this plugin needs
the Globals option set to true in order to function properly.

Plugin "smart"
The "smart" plugin collects SMART information from physical disks. Values
collectd include temperature, power cycle count, poweron time and bad sec-
tors. Also, all SMART attributes are collected along with the normalized
current value, the worst value, the threshold and a human readable value.
The plugin can also collect SMART attributes for NVMe disks (present in ac-
cordance with NVMe 1.4 spec) and Additional SMART Attributes from IntelA(R)
NVMe disks.

Using the following two options you can ignore some disks or configure the
collection only of specific disks.

Disk "sdd"
Disk "/hda[34]/"
Disk "nvme0n1"

See /"IGNORELISTS" for details.

IgnoreSleepMode true|false
Normally, the "smart" plugin will ignore disks that are reported to be
asleep. This option disables the sleep mode check and allows the plu-
gin to collect data from these disks anyway. This is useful in cases
where libatasmart mistakenly reports disks as asleep because it has not
been updated to incorporate support for newer idle states in the ATA
spec.

UseSerial true|false
A disk's kernel name (e.g., sda) can change from one boot to the next.
If this option is enabled, the "smart" plugin will use the disk's ser-
ial number (e.g., HGST_HUH728080ALE600_2EJ8VH8X) instead of the kernel
name as the key for storing data. This ensures that the data for a
given disk will be kept together even if the kernel name changes.

Plugin "snmp"
Since the configuration of the "snmp plugin" is a little more complicated
than other plugins, its documentation has been moved to an own manpage,
collectd-snmp(5). Please see there for details.

Plugin "snmp_agent"
The snmp_agent plugin is an AgentX subagent that receives and handles
queries from SNMP master agent and returns the data collected by read plug-
ins. The snmp_agent plugin handles requests only for OIDs specified in
configuration file. To handle SNMP queries the plugin gets data from col-
lectd and translates requested values from collectd's internal format to
SNMP format. This plugin is a generic plugin and cannot work without con-
figuration. For more details on AgentX subagent see
<http://www.net-snmp.org/tutorial/tutorial-5/toolkit/demon/>

Synopsis:

<Plugin snmp_agent>
<Data "memAvailReal">
Plugin "memory"
#PluginInstance "some"
Type "memory"
TypeInstance "free"
OIDs "1.3.6.1.4.1.2021.4.6.0"
</Data>
<Table "ifTable">
IndexOID "IF-MIB::ifIndex"
SizeOID "IF-MIB::ifNumber"
<Data "ifDescr">
<IndexKey>
Source "PluginInstance"
</IndexKey>
Plugin "interface"
OIDs "IF-MIB::ifDescr"
</Data>
<Data "ifOctets">
Plugin "interface"
Type "if_octets"
TypeInstance ""
OIDs "IF-MIB::ifInOctets" "IF-MIB::ifOutOctets"
</Data>
</Table>
<Table "CPUAffinityTable">
<Data "DomainName">
<IndexKey>
Source "PluginInstance"
</IndexKey>
Plugin "virt"
OIDs "LIBVIRT-HYPERVISOR-MIB::lvhAffinityDomainName"
</Data>
<Data "VCPU">
Plugin "virt"
<IndexKey>
Source "TypeInstance"
Regex "^vcpu_([0-9]{1,3})-cpu_[0-9]{1,3}$"
Group 1
</IndexKey>
OIDs "LIBVIRT-HYPERVISOR-MIB::lvhVCPUIndex"
</Data>
<Data "CPU">
Plugin "virt"
<IndexKey>
Source "TypeInstance"
Regex "^vcpu_[0-9]{1,3}-cpu_([0-9]{1,3})$"
Group 1
</IndexKey>
OIDs "LIBVIRT-HYPERVISOR-MIB::lvhCPUIndex"
</Data>
<Data "CPUAffinity">
Plugin "virt"
Type "cpu_affinity"
OIDs "LIBVIRT-HYPERVISOR-MIB::lvhCPUAffinity"
</Data>
</Table>
</Plugin>

There are two types of blocks that can be contained in the "<Plugin
snmp_agent>" block: Data and Table:

Data block

The Data block defines a list OIDs that are to be handled. This block can
define scalar or table OIDs. If Data block is defined inside of Table block
it reperesents table OIDs. The following options can be set:

IndexKey block
IndexKey block contains all data needed for proper index build of snmp
table. In case more than one table Data block has IndexKey block
present then multiple key index is built. If Data block defines scalar
data type IndexKey has no effect and can be omitted.

Source String
Source can be set to one of the following values: "Hostname",
"Plugin", "PluginInstance", "Type", "TypeInstance". This value
indicates which field of corresponding collectd metric is taken
as a SNMP table index.

Regex String
Regex option can also be used to parse strings or numbers out
of specific field. For example: type-instance field which is
"vcpu1-cpu2" can be parsed into two numeric fields CPU = 2 and
VCPU = 1 and can be later used as a table index.

Group Number
Group number can be specified in case groups are used in regex.

Plugin String
Read plugin name whose collected data will be mapped to specified OIDs.

PluginInstance String
Read plugin instance whose collected data will be mapped to specified
OIDs. The field is optional and by default there is no plugin instance
check. Allowed only if Data block defines scalar data type.

Type String
Collectd's type that is to be used for specified OID, e. g. "if_octets"
for example. The types are read from the TypesDB (see col-
lectd.conf(5)).

TypeInstance String
Collectd's type-instance that is to be used for specified OID.

OIDs OID [OID ...]
Configures the OIDs to be handled by snmp_agent plugin. Values for
these OIDs are taken from collectd data type specified by Plugin, Plug-
inInstance, Type, TypeInstance fields of this Data block. Number of the
OIDs configured should correspond to number of values in specified
Type. For example two OIDs "IF-MIB::ifInOctets" "IF-MIB::ifOutOctets"
can be mapped to "rx" and "tx" values of "if_octets" type.

Scale Value
The values taken from collectd are multiplied by Value. The field is
optional and the default is 1.0.

Shift Value
Value is added to values from collectd after they have been multiplied
by Scale value. The field is optional and the default value is 0.0.

The Table block

The Table block defines a collection of Data blocks that belong to one snmp
table. In addition to multiple Data blocks the following options can be
set:

IndexOID OID
OID that is handled by the plugin and is mapped to numerical index
value that is generated by the plugin for each table record.

SizeOID OID
OID that is handled by the plugin. Returned value is the number of
records in the table. The field is optional.

Plugin "statsd"
The statsd plugin listens to a UDP socket, reads "events" in the statsd
protocol and dispatches rates or other aggregates of these numbers periodi-
cally.

The plugin implements the Counter, Timer, Gauge and Set types which are
dispatched as the collectd types "derive", "latency", "gauge" and "objects"
respectively.

The following configuration options are valid:

Host Host
Bind to the hostname / address Host. By default, the plugin will bind
to the "any" address, i.e. accept packets sent to any of the hosts ad-
dresses.

Port Port
UDP port to listen to. This can be either a service name or a port num-
ber. Defaults to 8125.

DeleteCounters false|true
DeleteTimers false|true
DeleteGauges false|true
DeleteSets false|true
These options control what happens if metrics are not updated in an in-
terval. If set to False, the default, metrics are dispatched un-
changed, i.e. the rate of counters and size of sets will be zero,
timers report "NaN" and gauges are unchanged. If set to True, the such
metrics are not dispatched and removed from the internal cache.

CounterSum false|true
When enabled, creates a "count" metric which reports the change since
the last read. This option primarily exists for compatibility with the
statsd implementation by Etsy.

TimerPercentile Percent
Calculate and dispatch the configured percentile, i.e. compute the la-
tency, so that Percent of all reported timers are smaller than or equal
to the computed latency. This is useful for cutting off the long tail
latency, as it's often done in Service Level Agreements (SLAs).

Different percentiles can be calculated by setting this option several
times. If none are specified, no percentiles are calculated / dis-
patched.

TimerLower false|true
TimerUpper false|true
TimerSum false|true
TimerCount false|true
Calculate and dispatch various values out of Timer metrics received
during an interval. If set to False, the default, these values aren't
calculated / dispatched.

Please note what reported timer values less than 0.001 are ignored in
all Timer* reports.

Plugin "swap"
The Swap plugin collects information about used and available swap space.
On Linux and Solaris, the following options are available:

ReportByDevice false|true
Configures how to report physical swap devices. If set to false (the
default), the summary over all swap devices is reported only, i.e. the
globally used and available space over all devices. If true is config-
ured, the used and available space of each device will be reported sep-
arately.

This option is only available if the Swap plugin can read "/proc/swaps"
(under Linux) or use the swapctl(2) mechanism (under Solaris).

ReportBytes false|true
When enabled, the swap I/O is reported in bytes. When disabled, the de-
fault, swap I/O is reported in pages. This option is available under
Linux only.

ValuesAbsolute true|false
Enables or disables reporting of absolute swap metrics, i.e. number of
bytes available and used. Defaults to true.

ValuesPercentage false|true
Enables or disables reporting of relative swap metrics, i.e. percent
available and free. Defaults to false.

This is useful for deploying collectd in a heterogeneous environment,
where swap sizes differ and you want to specify generic thresholds or
similar.

ReportIO true|false
Enables or disables reporting swap IO. Defaults to true.

This is useful for the cases when swap IO is not neccessary, is not
available, or is not reliable.

Plugin "sysevent"
The sysevent plugin monitors rsyslog messages.

Synopsis:

<Plugin sysevent>
Listen "192.168.0.2" "6666"
BufferSize 1024
BufferLength 10
RegexFilter "regex"
</Plugin>

rsyslog should be configured such that it sends data to the IP and port you
include in the plugin configuration. For example, given the configuration
above, something like this would be set in /etc/rsyslog.conf:

if $programname != 'collectd' then
*.* @192.168.0.2:6666

This plugin is designed to consume JSON rsyslog data, so a more complete
rsyslog configuration would look like so (where we define a JSON template
and use it when sending data to our IP and port):

$template ls_json,"{%timestamp:::date-rfc3339,jsonf:@timestamp%, \
%source:::jsonf:@source_host%,\"@source\":\"syslog://%fromhost-ip:::json%\", \
\"@message\":\"%timestamp% %app-name%:%msg:::json%\",\"@fields\": \
{%syslogfacility-text:::jsonf:facility%,%syslogseverity:::jsonf:severity-num%, \
%syslogseverity-text:::jsonf:severity%,%programname:::jsonf:program%, \
%procid:::jsonf:processid%}}"

if $programname != 'collectd' then
*.* @192.168.0.2:6666;ls_json

Please note that these rsyslog.conf examples are *not* complete, as rsyslog
requires more than these options in the configuration file. These examples
are meant to demonstration the proper remote logging and JSON format syntax.

Options:

Listen host port
Listen on this IP on this port for incoming rsyslog messages.

BufferSize length
Maximum allowed size for incoming rsyslog messages. Messages that ex-
ceed this number will be truncated to this size. Default is 4096
bytes.

BufferLength length
Maximum number of rsyslog events that can be stored in plugin's ring
buffer. By default, this is set to 10. Once an event has been read,
its location becomes available for storing a new event.

RegexFilter regex
Enumerate a regex filter to apply to all incoming rsyslog messages. If
a message matches this filter, it will be published.

Plugin "syslog"
LogLevel debug|info|notice|warning|err
Sets the log-level. If, for example, set to notice, then all events
with severity notice, warning, or err will be submitted to the sys-
log-daemon.

Please note that debug is only available if collectd has been compiled
with debugging support.

NotifyLevel OKAY|WARNING|FAILURE
Controls which notifications should be sent to syslog. The default be-
haviour is not to send any. Less severe notifications always imply log-
ging more severe notifications: Setting this to OKAY means all notifi-
cations will be sent to syslog, setting this to WARNING will send WARN-
ING and FAILURE notifications but will dismiss OKAY notifications. Set-
ting this option to FAILURE will only send failures to syslog.

Plugin "table"
The "table plugin" provides generic means to parse tabular data and dis-
patch user specified values. Values are selected based on column numbers.
For example, this plugin may be used to get values from the Linux proc(5)
filesystem or CSV (comma separated values) files.

<Plugin table>
<Table "/proc/slabinfo">
#Plugin "slab"
Instance "slabinfo"
Separator " "
<Result>
Type gauge
InstancePrefix "active_objs"
InstancesFrom 0
ValuesFrom 1
</Result>
<Result>
Type gauge
InstancePrefix "objperslab"
InstancesFrom 0
ValuesFrom 4
</Result>
</Table>
</Plugin>

The configuration consists of one or more Table blocks, each of which con-
figures one file to parse. Within each Table block, there are one or more
Result blocks, which configure which data to select and how to interpret
it.

The following options are available inside a Table block:

Plugin Plugin
If specified, Plugin is used as the plugin name when submitting values.
Defaults to table.

Instance instance
If specified, instance is used as the plugin instance. If omitted, the
filename of the table is used instead, with all special characters re-
placed with an underscore ("_").

Separator string
Any character of string is interpreted as a delimiter between the dif-
ferent columns of the table. A sequence of two or more contiguous de-
limiters in the table is considered to be a single delimiter, i. e.
there cannot be any empty columns. The plugin uses the strtok_r(3)
function to parse the lines of a table - see its documentation for more
details. This option is mandatory.

A horizontal tab, newline and carriage return may be specified by
"\\t", "\\n" and "\\r" respectively. Please note that the double back-
slashes are required because of collectd's config parsing.

The following options are available inside a Result block:

Type type
Sets the type used to dispatch the values to the daemon. Detailed in-
formation about types and their configuration can be found in
types.db(5). This option is mandatory.

InstancePrefix prefix
If specified, prepend prefix to the type instance. If omitted, only the
InstancesFrom option is considered for the type instance.

InstancesFrom column0 [column1 ...]
If specified, the content of the given columns (identified by the col-
umn number starting at zero) will be used to create the type instance
for each row. Multiple values (and the instance prefix) will be joined
together with dashes (-) as separation character. If omitted, only the
InstancePrefix option is considered for the type instance.

The plugin itself does not check whether or not all built instances are
different. Itas your responsibility to assure that each is unique. This
is especially true, if you do not specify InstancesFrom: You have to
make sure that the table only contains one row.

If neither InstancePrefix nor InstancesFrom is given, the type instance
will be empty.

ValuesFrom column0 [column1 ...]
Specifies the columns (identified by the column numbers starting at
zero) whose content is used as the actual data for the data sets that
are dispatched to the daemon. How many such columns you need is deter-
mined by the Type setting above. If you specify too many or not enough
columns, the plugin will complain about that and no data will be sub-
mitted to the daemon. The plugin uses strtoll(3) and strtod(3) to parse
counter and gauge values respectively, so anything supported by those
functions is supported by the plugin as well. This option is mandatory.

Plugin "tail"
The "tail plugin" follows logfiles, just like tail(1) does, parses each
line and dispatches found values. What is matched can be configured by the
user using (extended) regular expressions, as described in regex(7).

<Plugin "tail">
<File "/var/log/exim4/mainlog">
Plugin "mail"
Instance "exim"
Interval 60
<Match>
Regex "S=([1-9][0-9]*)"
DSType "CounterAdd"
Type "ipt_bytes"
Instance "total"
</Match>
<Match>
Regex "\\<R=local_user\\>"
ExcludeRegex "\\<R=local_user\\>.*mail_spool defer"
DSType "CounterInc"
Type "counter"
Instance "local_user"
</Match>
<Match>
Regex "l=([0-9]*\\.[0-9]*)"
<DSType "Distribution">
Percentile 99
Bucket 0 100
#BucketType "bucket"
</DSType>
Type "latency"
Instance "foo"
</Match>
</File>
</Plugin>

The config consists of one or more File blocks, each of which configures
one logfile to parse. Within each File block, there are one or more Match
blocks, which configure a regular expression to search for.

The Plugin and Instance options in the File block may be used to set the
plugin name and instance respectively. So in the above example the plugin
name "mail-exim" would be used.

These options are applied for all Match blocks that follow it, until the
next Plugin or Instance option. This way you can extract several plugin in-
stances from one logfile, handy when parsing syslog and the like.

The Interval option allows you to define the length of time between reads.
If this is not set, the default Interval will be used.

Each Match block has the following options to describe how the match should
be performed:

Regex regex
Sets the regular expression to use for matching against a line. The
first subexpression has to match something that can be turned into a
number by strtoll(3) or strtod(3), depending on the value of "Counter-
Add", see below. Because extended regular expressions are used, you do
not need to use backslashes for subexpressions! If in doubt, please
consult regex(7). Due to collectd's config parsing you need to escape
backslashes, though. So if you want to match literal parentheses you
need to do the following:

Regex "SPAM \$Score: (-?[0-9]+\\.[0-9]+)\$"

ExcludeRegex regex
Sets an optional regular expression to use for excluding lines from the
match. An example which excludes all connections from localhost from
the match:

ExcludeRegex "127\\.0\\.0\\.1"

DSType Type
Sets how the values are cumulated. Type is one of:

GaugeAverage
Calculate the average of all values matched during the interval.

GaugeMin
Report the smallest value matched during the interval.

GaugeMax
Report the greatest value matched during the interval.

GaugeLast
Report the last value matched during the interval.

GaugePersist
Report the last matching value. The metric is not reset to "NaN" at
the end of an interval. It is continuously reported until another
value is matched. This is intended for cases in which only state
changes are reported, for example a thermometer that only reports
the temperature when it changes.

CounterSet
DeriveSet
AbsoluteSet
The matched number is a counter. Simply sets the internal counter
to this value. Variants exist for "COUNTER", "DERIVE", and "AB-
SOLUTE" data sources.

GaugeAdd
CounterAdd
DeriveAdd
Add the matched value to the internal counter. In case of De-
riveAdd, the matched number may be negative, which will effectively
subtract from the internal counter.

GaugeInc
CounterInc
DeriveInc
Increase the internal counter by one. These DSType are the only
ones that do not use the matched subexpression, but simply count
the number of matched lines. Thus, you may use a regular expression
without submatch in this case.

GaugeInc is reset to zero after every read, unlike other Gauge*
metrics which are reset to "NaN".

Distribution
Type to do calculations based on the distribution of values, pri-
marily calculating percentiles. This is primarily geared towards
latency, but can be used for other metrics as well. The range of
values tracked with this setting must be in the range (0a2^34) and
can be fractional. Please note that neither zero nor 2^34 are in-
clusive bounds, i.e. zero cannot be handled by a distribution.

This option must be used together with the Percentile and/or Bucket
options.

Synopsis:

<DSType "Distribution">
Percentile 99
Bucket 0 100
BucketType "bucket"
</DSType>

Percentile Percent
Calculate and dispatch the configured percentile, i.e. compute
the value, so that Percent of all matched values are smaller
than or equal to the computed latency.

Metrics are reported with the type Type (the value of the above
option) and the type instance "[<Instance>-]<Percent>".

This option may be repeated to calculate more than one per-
centile.

Bucket lower_bound upper_bound
Export the number of values (a "DERIVE") falling within the
given range. Both, lower_bound and upper_bound may be a frac-
tional number, such as 0.5. Each Bucket option specifies an
interval "(lower_bound, upper_bound]", i.e. the range excludes
the lower bound and includes the upper bound. lower_bound and
upper_bound may be zero, meaning no lower/upper bound.

To export the entire (0ainf) range without overlap, use the up-
per bound of the previous range as the lower bound of the fol-
lowing range. In other words, use the following schema:

Bucket 0 1
Bucket 1 2
Bucket 2 5
Bucket 5 10
Bucket 10 20
Bucket 20 50
Bucket 50 0

Metrics are reported with the type set by BucketType option
("bucket" by default) and the type instance "<Type>[-<In-
stance>]-<lower_bound>_<upper_bound>".

This option may be repeated to calculate more than one rate.

BucketType Type
Sets the type used to dispatch Bucket metrics. Optional, by
default "bucket" will be used.

The Gauge* and Distribution types interpret the submatch as a floating
point number, using strtod(3). The Counter* and AbsoluteSet types in-
terpret the submatch as an unsigned integer using strtoull(3). The De-
rive* types interpret the submatch as a signed integer using str-
toll(3). CounterInc, DeriveInc and GaugeInc do not use the submatch at
all and it may be omitted in this case.

The Gauge* types, unless noted otherwise, are reset to "NaN" after be-
ing reported. In other words, GaugeAverage reports the average of all
values matched since the last metric was reported (or "NaN" if there
was no match).

Type Type
Sets the type used to dispatch this value. Detailed information about
types and their configuration can be found in types.db(5).

Instance TypeInstance
This optional setting sets the type instance to use.

Plugin "tail_csv"
The tail_csv plugin reads files in the CSV format, e.g. the statistics file
written by Snort.

Synopsis:

<Plugin "tail_csv">
<Metric "snort-dropped">
Type "percent"
Instance "dropped"
ValueFrom 1
</Metric>
<File "/var/log/snort/snort.stats">
Plugin "snortstats"
Instance "eth0"
Interval 600
Collect "snort-dropped"
FieldSeparator ","
#TimeFrom 0
</File>
</Plugin>

The configuration consists of one or more Metric blocks that define an in-
dex into the line of the CSV file and how this value is mapped to col-
lectd's internal representation. These are followed by one or more Instance
blocks which configure which file to read, in which interval and which met-
rics to extract.

<Metric Name>
The Metric block configures a new metric to be extracted from the sta-
tistics file and how it is mapped on collectd's data model. The string
Name is only used inside the Instance blocks to refer to this block, so
you can use one Metric block for multiple CSV files.

Type Type
Configures which Type to use when dispatching this metric. Types
are defined in the types.db(5) file, see the appropriate manual
page for more information on specifying types. Only types with a
single data source are supported by the tail_csv plugin. The infor-
mation whether the value is an absolute value (i.e. a "GAUGE") or a
rate (i.e. a "DERIVE") is taken from the Type's definition.

Instance TypeInstance
If set, TypeInstance is used to populate the type instance field of
the created value lists. Otherwise, no type instance is used.

ValueFrom Index
Configure to read the value from the field with the zero-based in-
dex Index. If the value is parsed as signed integer, unsigned in-
teger or double depends on the Type setting, see above.

<File Path>
Each File block represents one CSV file to read. There must be at least
one File block but there can be multiple if you have multiple CSV
files.

Plugin Plugin
Use Plugin as the plugin name when submitting values. Defaults to
"tail_csv".

Instance PluginInstance
Sets the plugin instance used when dispatching the values.

Collect Metric
Specifies which Metric to collect. This option must be specified at
least once, and you can use this option multiple times to specify
more than one metric to be extracted from this statistic file.

Interval Seconds
Configures the interval in which to read values from this instance
/ file. Defaults to the plugin's default interval.

TimeFrom Index
Rather than using the local time when dispatching a value, read the
timestamp from the field with the zero-based index Index. The value
is interpreted as seconds since epoch. The value is parsed as a
double and may be factional.

FieldSeparator Character
Specify the character to use as field separator while parsing the
CSV. Defaults to ',' if not specified. The value can only be a
single character.

Plugin "teamspeak2"
The "teamspeak2 plugin" connects to the query port of a teamspeak2 server
and polls interesting global and virtual server data. The plugin can query
only one physical server but unlimited virtual servers. You can use the
following options to configure it:

Host hostname/ip
The hostname or ip which identifies the physical server. Default:
127.0.0.1

Port port
The query port of the physical server. This needs to be a string. De-
fault: "51234"

Server port
This option has to be added once for every virtual server the plugin
should query. If you want to query the virtual server on port 8767 this
is what the option would look like:

Server "8767"

This option, although numeric, needs to be a string, i. e. you must use
quotes around it! If no such statement is given only global information
will be collected.

Plugin "ted"
The TED plugin connects to a device of "The Energy Detective", a device to
measure power consumption. These devices are usually connected to a serial
(RS232) or USB port. The plugin opens a configured device and tries to read
the current energy readings. For more information on TED, visit
<http://www.theenergydetective.com/>.

Available configuration options:

Device Path
Path to the device on which TED is connected. collectd will need read
and write permissions on that file.

Default: /dev/ttyUSB0

Retries Num
Apparently reading from TED is not that reliable. You can therefore
configure a number of retries here. You only configure the retries
here, to if you specify zero, one reading will be performed (but no re-
tries if that fails); if you specify three, a maximum of four readings
are performed. Negative values are illegal.

Default: 0

Plugin "tcpconns"
The "tcpconns plugin" counts the number of currently established TCP con-
nections based on the local port and/or the remote port. Since there may be
a lot of connections the default if to count all connections with a local
port, for which a listening socket is opened. You can use the following op-
tions to fine-tune the ports you are interested in:

ListeningPorts true|false
If this option is set to true, statistics for all local ports for which
a listening socket exists are collected. The default depends on Local-
Port and RemotePort (see below): If no port at all is specifically se-
lected, the default is to collect listening ports. If specific ports
(no matter if local or remote ports) are selected, this option defaults
to false, i. e. only the selected ports will be collected unless this
option is set to true specifically.

LocalPort Port
Count the connections to a specific local port. This can be used to see
how many connections are handled by a specific daemon, e. g. the
mailserver. You have to specify the port in numeric form, so for the
mailserver example you'd need to set 25.

RemotePort Port
Count the connections to a specific remote port. This is useful to see
how much a remote service is used. This is most useful if you want to
know how many connections a local service has opened to remote ser-
vices, e. g. how many connections a mail server or news server has to
other mail or news servers, or how many connections a web proxy holds
to web servers. You have to give the port in numeric form.

AllPortsSummary true|false
If this option is set to true a summary of statistics from all connec-
tions are collected. This option defaults to false.

Plugin "thermal"
ForceUseProcfs true|false
By default, the Thermal plugin tries to read the statistics from the
Linux "sysfs" interface. If that is not available, the plugin falls
back to the "procfs" interface. By setting this option to true, you can
force the plugin to use the latter. This option defaults to false.

Device Device
Selects the name of the thermal device that you want to collect or ig-
nore, depending on the value of the IgnoreSelected option. This option
may be used multiple times to specify a list of devices.

See /"IGNORELISTS" for details.

IgnoreSelected true|false
Invert the selection: If set to true, all devices except the ones that
match the device names specified by the Device option are collected. By
default only selected devices are collected if a selection is made. If
no selection is configured at all, all devices are selected.

Plugin "threshold"
The Threshold plugin checks values collected or received by collectd
against a configurable threshold and issues notifications if values are out
of bounds.

Documentation for this plugin is available in the collectd-threshold(5)
manual page.

Plugin "tokyotyrant"
The TokyoTyrant plugin connects to a TokyoTyrant server and collects a cou-
ple metrics: number of records, and database size on disk.

Host Hostname/IP
The hostname or IP which identifies the server. Default: 127.0.0.1

Port Service/Port
The query port of the server. This needs to be a string, even if the
port is given in its numeric form. Default: 1978

Plugin "turbostat"
The Turbostat plugin reads CPU frequency and C-state residency on modern
Intel processors by using Model Specific Registers.

CoreCstates Bitmask(Integer)
Bit mask of the list of core C-states supported by the processor. This
option should only be used if the automated detection fails. Default
value extracted from the CPU model and family.

Currently supported C-states (by this plugin): 3, 6, 7

Example:

All states (3, 6 and 7):
(1<<3) + (1<<6) + (1<<7) = 392

PackageCstates Bitmask(Integer)
Bit mask of the list of packages C-states supported by the processor.
This option should only be used if the automated detection fails. De-
fault value extracted from the CPU model and family.

Currently supported C-states (by this plugin): 2, 3, 6, 7, 8, 9, 10

Example:

States 2, 3, 6 and 7:
(1<<2) + (1<<3) + (1<<6) + (1<<7) = 396

SystemManagementInterrupt true|false
Boolean enabling the collection of the I/O System-Management Interrupt
counter. This option should only be used if the automated detection
fails or if you want to disable this feature.

DigitalTemperatureSensor true|false
Boolean enabling the collection of the temperature of each core. This
option should only be used if the automated detection fails or if you
want to disable this feature.

TCCActivationTemp Temperature
Thermal Control Circuit Activation Temperature of the installed CPU.
This temperature is used when collecting the temperature of cores or
packages. This option should only be used if the automated detection
fails. Default value extracted from MSR_IA32_TEMPERATURE_TARGET.

RunningAveragePowerLimit Bitmask(Integer)
Bit mask of the list of elements to be thermally monitored. This option
should only be used if the automated detection fails or if you want to
disable some collections. The different bits of this bit mask accepted
by this plugin are:

0 ('1'): Package
1 ('2'): DRAM
2 ('4'): Cores
3 ('8'): Embedded graphic device

LogicalCoreNames true|false
Boolean enabling the use of logical core numbering for per core statis-
tics. When enabled, "cpu<n>" is used as plugin instance, where n is a
dynamic number assigned by the kernel. Otherwise, "core<n>" is used if
there is only one package and "pkg<n>-core<m>" if there is more than
one, where n is the n-th core of package m.

RestoreAffinityPolicy AllCPUs|Restore
Reading data from CPU has side-effect: collectd process's CPU affinity
mask changes. After reading data is completed, affinity mask needs to
be restored. This option allows to set restore policy.

AllCPUs (the default): Restore the affinity by setting affinity to
any/all CPUs.

Restore: Save affinity using sched_getaffinity() before reading data
and restore it after.

On some systems, sched_getaffinity() will fail due to inconsistency of
the CPU set size between userspace and kernel. In these cases plugin
will detect the unsuccessful call and fail with an error, preventing
data collection. Most of configurations does not need to save affinity
as Collectd process is allowed to run on any/all available CPUs.

If you need to save and restore affinity and get errors like 'Unable to
save the CPU affinity', setting 'possible_cpus' kernel boot option may
also help.

See following links for details:

<https://github.com/collectd/collectd/issues/1593> <https://source-
ware.org/bugzilla/show_bug.cgi?id=15630> <https://bugzilla.ker-
nel.org/show_bug.cgi?id=151821>

Plugin "ubi"
The Ubi plugin collects some statistics about the UBI (Unsorted Block Im-
age). Values collected are the number of bad physical eraseblocks on the
underlying MTD (Memory Technology Device) and the maximum erase counter
value concerning one volume.

See following links for details:

<http://www.linux-mtd.infradead.org/doc/ubi.html> <http://www.linux-mtd.in-
fradead.org/doc/ubifs.html> <https://www.kernel.org/doc/Documenta-
tion/ABI/stable/sysfs-class-ubi>

Device Name
Select the device Name of the UBI volume. Whether it is collected or
ignored depends on the IgnoreSelected setting, see below.

See /"IGNORELISTS" for details.

IgnoreSelected true|false
Sets whether selected devices, i. e. the ones matches by any of the De-
vice statements, are ignored or if all other devices are ignored. If no
Device option is configured, all devices are collected. If at least one
Device is given and no IgnoreSelected or set to false, only matching
disks will be collected. If IgnoreSelectedis set to true, all devices
are collected except the ones matched.

Plugin "unixsock"
SocketFile Path
Sets the socket-file which is to be created.

SocketGroup Group
If running as root change the group of the UNIX-socket after it has
been created. Defaults to collectd.

DeleteSocket false|true
If set to true, delete the socket file before calling bind(2), if a
file with the given name already exists. If collectd crashes a socket
file may be left over, preventing the daemon from opening a new socket
when restarted. Since this is potentially dangerous, this defaults to
false.

Plugin "uuid"
This plugin, if loaded, causes the Hostname to be taken from the machine's
UUID. The UUID is a universally unique designation for the machine, usually
taken from the machine's BIOS. This is most useful if the machine is run-
ning in a virtual environment such as Xen, in which case the UUID is pre-
served across shutdowns and migration.

The following methods are used to find the machine's UUID, in order:

* Check /etc/uuid (or UUIDFile).

* Check for UUID from HAL (<http://www.freedesktop.org/wiki/Soft-
ware/hal>) if present.

* Check for UUID from "dmidecode" / SMBIOS.

* Check for UUID from Xen hypervisor.

If no UUID can be found then the hostname is not modified.

UUIDFile Path
Take the UUID from the given file (default /etc/uuid).

Plugin "varnish"
The varnish plugin collects information about Varnish, an HTTP accelerator.
It collects a subset of the values displayed by varnishstat(1), and orga-
nizes them in categories which can be enabled or disabled. Currently only
metrics shown in varnishstat(1)'s MAIN section are collected. The exact
meaning of each metric can be found in varnish-counters(7).

Synopsis:

<Plugin "varnish">
<Instance "example">
CollectBackend true
CollectBan false
CollectCache true
CollectConnections true
CollectDirectorDNS false
CollectESI false
CollectFetch false
CollectHCB false
CollectObjects false
CollectPurge false
CollectSession false
CollectSHM true
CollectSMA false
CollectSMS false
CollectSM false
CollectStruct false
CollectTotals false
CollectUptime false
CollectVCL false
CollectVSM false
CollectWorkers false
CollectLock false
CollectMempool false
CollectManagement false
CollectSMF false
CollectVBE false
CollectMSE false
</Instance>
</Plugin>

The configuration consists of one or more <Instance Name> blocks. Name is
the parameter passed to "varnishd -n". If left empty, it will collectd sta-
tistics from the default "varnishd" instance (this should work fine in most
cases).

Inside each <Instance> blocks, the following options are recognized:

CollectBackend true|false
Back-end connection statistics, such as successful, reused, and closed
connections. True by default.

CollectBan true|false
Statistics about ban operations, such as number of bans added, retired,
and number of objects tested against ban operations. Only available
with Varnish 3.x and above. False by default.

CollectCache true|false
Cache hits and misses. True by default.

CollectConnections true|false
Number of client connections received, accepted and dropped. True by
default.

CollectDirectorDNS true|false
DNS director lookup cache statistics. Only available with Varnish 3.x.
False by default.

CollectESI true|false
Edge Side Includes (ESI) parse statistics. False by default.

CollectFetch true|false
Statistics about fetches (HTTP requests sent to the backend). False by
default.

CollectHCB true|false
Inserts and look-ups in the crit bit tree based hash. Look-ups are di-
vided into locked and unlocked look-ups. False by default.

CollectObjects true|false
Statistics on cached objects: number of objects expired, nuked (prema-
turely expired), saved, moved, etc. False by default.

CollectPurge true|false
Statistics about purge operations, such as number of purges added, re-
tired, and number of objects tested against purge operations. Only
available with Varnish 2.x. False by default.

CollectSession true|false
Client session statistics. Number of past and current sessions, session
herd and linger counters, etc. False by default. Note that if using
Varnish 4.x, some metrics found in the Connections and Threads sections
with previous versions of Varnish have been moved here.

CollectSHM true|false
Statistics about the shared memory log, a memory region to store log
messages which is flushed to disk when full. True by default.

CollectSMA true|false
malloc or umem (umem_alloc(3MALLOC) based) storage statistics. The umem
storage component is Solaris specific. Note: SMA, SMF and MSE share
counters, enable only the one used by the Varnish instance. Available
with Varnish 2.x, varnish 4.x and above (Not available in varnish 3.x).
False by default.

CollectSMS true|false
synth (synthetic content) storage statistics. This storage component is
used internally only. False by default.

CollectSM true|false
file (memory mapped file) storage statistics. Only available with Var-
nish 2.x, in varnish 4.x and above use CollectSMF. False by default.

CollectStruct true|false
Current varnish internal state statistics. Number of current sessions,
objects in cache store, open connections to backends (with Varnish
2.x), etc. False by default.

CollectTotals true|false
Collects overview counters, such as the number of sessions created, the
number of requests and bytes transferred. False by default.

CollectUptime true|false
Varnish uptime. Only available with Varnish 3.x and above. False by de-
fault.

CollectVCL true|false
Number of total (available + discarded) VCL (config files). False by
default.

CollectVSM true|false
Collect statistics about Varnish's shared memory usage (used by the
logging and statistics subsystems). Only available with Varnish 4.x.
False by default.

CollectWorkers true|false
Collect statistics about worker threads. False by default.

CollectVBE true|false
Backend counters. Only available with Varnish 4.x and above. False by
default.

CollectSMF true|false
file (memory mapped file) storage statistics. Only available with Var-
nish 4.x and above. Note: SMA, SMF and MSE share counters, enable only
the one used by the Varnish instance. Used to be called SM in Varnish
2.x. False by default.

CollectManagement true|false
Management process counters. Only available with Varnish 4.x and above.
False by default.

CollectLock true|false
Lock counters. Only available with Varnish 4.x and above. False by de-
fault.

CollectMempool true|false
Memory pool counters. Only available with Varnish 4.x and above. False
by default.

CollectMSE true|false
Varnish Massive Storage Engine 2.0 (MSE2) is an improved storage back-
end for Varnish, replacing the traditional malloc and file storages.
Only available with Varnish-Plus 4.x and above. Note: SMA, SMF and MSE
share counters, enable only the one used by the Varnish instance. False
by default.

CollectGOTO true|false
vmod-goto counters. Only available with Varnish Plus 6.x. False by de-
fault.

Plugin "virt"
This plugin allows CPU, disk, network load and other metrics to be col-
lected for virtualized guests on the machine. The statistics are collected
through libvirt API (<http://libvirt.org/>). Majority of metrics can be
gathered without installing any additional software on guests, especially
collectd, which runs only on the host system.

Only Connection is required.

Consider the following example config:

<Plugin "virt">
Connection "qemu:///system"
HostnameFormat "hostname"
InterfaceFormat "address"
PluginInstanceFormat "name"
</Plugin>

It will generate the following values:

node42.example.com/virt-instance-0006f26c/disk_octets-vda
node42.example.com/virt-instance-0006f26c/disk_ops-vda
node42.example.com/virt-instance-0006f26c/if_dropped-ca:fe:ca:fe:ca:fe
node42.example.com/virt-instance-0006f26c/if_errors-ca:fe:ca:fe:ca:fe
node42.example.com/virt-instance-0006f26c/if_octets-ca:fe:ca:fe:ca:fe
node42.example.com/virt-instance-0006f26c/if_packets-ca:fe:ca:fe:ca:fe
node42.example.com/virt-instance-0006f26c/memory-actual_balloon
node42.example.com/virt-instance-0006f26c/memory-available
node42.example.com/virt-instance-0006f26c/memory-last_update
node42.example.com/virt-instance-0006f26c/memory-major_fault
node42.example.com/virt-instance-0006f26c/memory-minor_fault
node42.example.com/virt-instance-0006f26c/memory-rss
node42.example.com/virt-instance-0006f26c/memory-swap_in
node42.example.com/virt-instance-0006f26c/memory-swap_out
node42.example.com/virt-instance-0006f26c/memory-total
node42.example.com/virt-instance-0006f26c/memory-unused
node42.example.com/virt-instance-0006f26c/memory-usable
node42.example.com/virt-instance-0006f26c/virt_cpu_total
node42.example.com/virt-instance-0006f26c/virt_vcpu-0

You can get information on the metric's units from the online libvirt docu-
mentation. For instance, virt_cpu_total is in nanoseconds.

Connection uri
Connect to the hypervisor given by uri. For example if using Xen use:

Connection "xen:///"

Details which URIs allowed are given at <http://libvirt.org/uri.html>.

RefreshInterval seconds
Refresh the list of domains and devices every seconds. The default is
60 seconds. Setting this to be the same or smaller than the Interval
will cause the list of domains and devices to be refreshed on every it-
eration.

Refreshing the devices in particular is quite a costly operation, so if
your virtualization setup is static you might consider increasing this.
If this option is set to 0, refreshing is disabled completely.

Domain name
BlockDevice name:dev
InterfaceDevice name:dev
IgnoreSelected true|false
Select which domains and devices are collected.

If IgnoreSelected is not given or false then only the listed domains
and disk/network devices are collected.

If IgnoreSelected is true then the test is reversed and the listed do-
mains and disk/network devices are ignored, while the rest are col-
lected.

The domain name and device names may use a regular expression, if the
name is surrounded by /.../ and collectd was compiled with support for
regexps.

The default is to collect statistics for all domains and all their de-
vices.

Note: BlockDevice and InterfaceDevice options are related to corre-
sponding *Format options. Specifically, BlockDevice filtering depends
on BlockDeviceFormat setting - if user wants to filter block devices by
'target' name then BlockDeviceFormat option has to be set to 'target'
and BlockDevice option must be set to a valid block device target
name("/:hdb/"). Mixing formats and filter values from different worlds
(i.e., using 'target' name as BlockDevice value with BlockDeviceFormat
set to 'source') may lead to unexpected results (all devices filtered
out or all visible, depending on the value of IgnoreSelected option).
Similarly, option InterfaceDevice is related to InterfaceFormat setting
(i.e., when user wants to use MAC address as a filter then Interface-
Format has to be set to 'address' - using wrong type here may filter
out all of the interfaces).

Example 1:

Ignore all hdb devices on any domain, but other block devices (eg. hda)
will be collected:

BlockDevice "/:hdb/"
IgnoreSelected "true"
BlockDeviceFormat "target"

Example 2:

Collect metrics only for block device on 'baremetal0' domain when its
'source' matches given path:

BlockDevice "baremetal0:/var/db/libvirt/images/baremetal0.qcow2"
BlockDeviceFormat source

As you can see it is possible to filter devices/interfaces using vari-
ous formats - for block devices 'target' or 'source' name can be used.
Interfaces can be filtered using 'name', 'address' or 'number'.

Example 3:

Collect metrics only for domains 'baremetal0' and 'baremetal1' and ig-
nore any other domain:

Domain "baremetal0"
Domain "baremetal1"

It is possible to filter multiple block devices/domains/interfaces by
adding multiple filtering entries in separate lines.

BlockDeviceFormat target|source
If BlockDeviceFormat is set to target, the default, then the device
name seen by the guest will be used for reporting metrics. This corre-
sponds to the "<target>" node in the XML definition of the domain.

If BlockDeviceFormat is set to source, then metrics will be reported
using the path of the source, e.g. an image file. This corresponds to
the "<source>" node in the XML definition of the domain.

Example:

If the domain XML have the following device defined:

Setting "BlockDeviceFormat target" will cause the type instance to be
set to "sda". Setting "BlockDeviceFormat source" will cause the type
instance to be set to "var_lib_libvirt_images_image1.qcow2".

Note: this option determines also what field will be used for filtering
over block devices (filter value in BlockDevice will be applied to tar-
get or source). More info about filtering block devices can be found in
the description of BlockDevice.

BlockDeviceFormatBasename false|true
The BlockDeviceFormatBasename controls whether the full path or the
basename(1) of the source is being used as the type instance when
BlockDeviceFormat is set to source. Defaults to false.

Example:

Assume the device path (source tag) is "/var/db/libvirt/images/im-
age1.qcow2". Setting "BlockDeviceFormatBasename false" will cause the
type instance to be set to "var_lib_libvirt_images_image1.qcow2". Set-
ting "BlockDeviceFormatBasename true" will cause the type instance to
be set to "image1.qcow2".

HostnameFormat name|uuid|hostname|metadata...
When the virt plugin logs data, it sets the hostname of the collected
data according to this setting. The default is to use the guest name as
provided by the hypervisor, which is equal to setting name.

uuid means use the guest's UUID. This is useful if you want to track
the same guest across migrations.

hostname means to use the global Hostname setting, which is probably
not useful on its own because all guests will appear to have the same
name. This is useful in conjunction with PluginInstanceFormat though.

metadata means use information from guest's metadata. Use HostnameMeta-
dataNS and HostnameMetadataXPath to localize this information.

You can also specify combinations of these fields. For example name
uuid means to concatenate the guest name and UUID (with a literal colon
character between, thus "foo:1234-1234-1234-1234").

At the moment of writing (collectd-5.5), hostname string is limited to
62 characters. In case when combination of fields exceeds 62 charac-
ters, hostname will be truncated without a warning.

InterfaceFormat name|address|number
When the virt plugin logs interface data, it sets the name of the col-
lected data according to this setting. The default is to use the path
as provided by the hypervisor (the "dev" property of the target node),
which is equal to setting name.

address means use the interface's mac address. This is useful since the
interface path might change between reboots of a guest or across migra-
tions.

number means use the interface's number in guest.

Note: this option determines also what field will be used for filtering
over interface device (filter value in InterfaceDevice will be applied
to name, address or number). More info about filtering interfaces can
be found in the description of InterfaceDevice.

PluginInstanceFormat name|uuid|metadata|none
When the virt plugin logs data, it sets the plugin_instance of the col-
lected data according to this setting. The default is to not set the
plugin_instance.

name means use the guest's name as provided by the hypervisor. uuid
means use the guest's UUID. metadata means use information from
guest's metadata.

You can also specify combinations of the name and uuid fields. For ex-
ample name uuid means to concatenate the guest name and UUID (with a
literal colon character between, thus "foo:1234-1234-1234-1234").

HostnameMetadataNS string
When metadata is used in HostnameFormat or PluginInstanceFormat, this
selects in which metadata namespace we will pick the hostname. The de-
fault is http://openstack.org/xmlns/libvirt/nova/1.0.

HostnameMetadataXPath string
When metadata is used in HostnameFormat or PluginInstanceFormat, this
describes where the hostname is located in the libvirt metadata. The
default is /instance/name/text().

ReportBlockDevices true|false
Enabled by default. Allows to disable stats reporting of block devices
for whole plugin.

ReportNetworkInterfaces true|false
Enabled by default. Allows to disable stats reporting of network inter-
faces for whole plugin.

ExtraStats string
Report additional extra statistics. The default is no extra statistics,
preserving the previous behaviour of the plugin. If unsure, leave the
default. If enabled, allows the plugin to reported more detailed sta-
tistics about the behaviour of Virtual Machines. The argument is a
space-separated list of selectors.

Currently supported selectors are:

cpu_util: report CPU utilization per domain in percentage.
disk: report extra statistics like number of flush operations and total
service time for read, write and flush operations. Requires libvirt API
version 0.9.5 or later.
disk_err: report disk errors if any occured. Requires libvirt API ver-
sion 0.9.10 or later.
domain_state: report domain state and reason as 'domain_state' metric.
fs_info: report file system information as a notification. Requires
libvirt API version 1.2.11 or later. Can be collected only if Guest
Agent is installed and configured inside VM. Make sure that installed
Guest Agent version supports retrieving file system information.
job_stats_background: report statistics about progress of a background
job on a domain. Only one type of job statistics can be collected at
the same time. Requires libvirt API version 1.2.9 or later.
job_stats_completed: report statistics about a recently completed job
on a domain. Only one type of job statistics can be collected at the
same time. Requires libvirt API version 1.2.9 or later.
memory: report statistics about memory usage details, provided by lib-
virt virDomainMemoryStats() function.
pcpu: report the physical user/system cpu time consumed by the hypervi-
sor, per-vm. Requires libvirt API version 0.9.11 or later.
perf: report performance monitoring events. To collect performance met-
rics they must be enabled for domain and supported by the platform. Re-
quires libvirt API version 1.3.3 or later. Note: perf metrics can't be
collected if intel_rdt plugin is enabled.
vcpu: report domain virtual CPUs utilisation.
vcpupin: report pinning of domain VCPUs to host physical CPUs.
disk_physical: report 'disk_physical' statistic for disk device. Note:
This statistic is only reported for disk devices with 'source' property
available.
disk_allocation: report 'disk_allocation' statistic for disk device.
Note: This statistic is only reported for disk devices with 'source'
property available.
disk_capacity: report 'disk_capacity' statistic for disk device. Note:
This statistic is only reported for disk devices with 'source' property
available.

PersistentNotification true|false
Override default configuration to only send notifications when there is
a change in the lifecycle state of a domain. When set to true notifica-
tions will be sent for every read cycle. Default is false. Does not af-
fect the stats being dispatched.

Instances integer
How many read instances you want to use for this plugin. The default is
one, and the sensible setting is a multiple of the ReadThreads value.

This option is only useful when domains are specially tagged. If you
are not sure, just use the default setting.

The reader instance will only query the domains with attached matching
tag. Tags should have the form of 'virt-X' where X is the reader in-
stance number, starting from 0.

The special-purpose reader instance #0, guaranteed to be always
present, will query all the domains with missing or unrecognized tag,
so no domain will ever be left out.

Domain tagging is done with a custom attribute in the libvirt domain
metadata section. Value is selected by an XPath /domain/meta-
data/ovirtmap/tag/text() expression in the
http://ovirt.org/ovirtmap/tag/1.0 namespace. (XPath and namespace val-
ues are not configurable yet).

Tagging could be used by management applications to evenly spread the
load among the reader threads, or to pin on the same threads all the
libvirt domains which use the same shared storage, to minimize the dis-
ruption in presence of storage outages.

Plugin "vmem"
The "vmem" plugin collects information about the usage of virtual memory.
Since the statistics provided by the Linux kernel are very detailed, they
are collected very detailed. However, to get all the details, you have to
switch them on manually. Most people just want an overview over, such as
the number of pages read from swap space.

Verbose true|false
Enables verbose collection of information. This will start collecting
page "actions", e. g. page allocations, (de)activations, steals and so
on. Part of these statistics are collected on a "per zone" basis.

Plugin "vserver"
This plugin doesn't have any options. VServer support is only available for
Linux. It cannot yet be found in a vanilla kernel, though. To make use of
this plugin you need a kernel that has VServer support built in, i. e. you
need to apply the patches and compile your own kernel, which will then pro-
vide the /proc/virtual filesystem that is required by this plugin.

The VServer homepage can be found at <http://linux-vserver.org/>.

Note: The traffic collected by this plugin accounts for the amount of traf-
fic passing a socket which might be a lot less than the actual on-wire
traffic (e. g. due to headers and retransmission). If you want to collect
on-wire traffic you could, for example, use the logging facilities of ipta-
bles to feed data for the guest IPs into the iptables plugin.

Plugin "write_graphite"
The "write_graphite" plugin writes data to Graphite, an open-source metrics
storage and graphing project. The plugin connects to Carbon, the data layer
of Graphite, via TCP or UDP and sends data via the "line based" protocol
(per default using port 2003). The data will be sent in blocks of at most
1428 bytes to minimize the number of network packets.

Synopsis:

<Plugin write_graphite>
<Node "example">
Host "localhost"
Port "2003"
Protocol "tcp"
LogSendErrors true
Prefix "collectd"
UseTags false
ReverseHost false
</Node>
</Plugin>

The configuration consists of one or more <Node Name> blocks. Inside the
Node blocks, the following options are recognized:

Host Address
Hostname or address to connect to. Defaults to "localhost".

Port Service
Service name or port number to connect to. Defaults to 2003.

Protocol String
Protocol to use when connecting to Graphite. Defaults to "tcp".

ReconnectInterval Seconds
When set to non-zero, forces the connection to the Graphite backend to
be closed and re-opend periodically. This behavior is desirable in en-
vironments where the connection to the Graphite backend is done through
load balancers, for example. When set to zero, the default, the con-
netion is kept open for as long as possible.

LogSendErrors false|true
If set to true (the default), logs errors when sending data to
Graphite. If set to false, it will not log the errors. This is espe-
cially useful when using Protocol UDP since many times we want to use
the "fire-and-forget" approach and logging errors fills syslog with un-
needed messages.

Prefix String
When UseTags is false, Prefix value is added in front of the host name.
When UseTags is true, Prefix value is added in front of series name.

Dots and whitespace are not escaped in this string (see EscapeCharacter
below).

Postfix String
When UseTags is false, Postfix value appended to the host name. When
UseTags is true, Postgix value appended to the end of series name (be-
fore the first ; that separates the name from the tags).

Dots and whitespace are not escaped in this string (see EscapeCharacter
below).

EscapeCharacter Char
Carbon uses the dot (".") as escape character and doesn't allow white-
space in the identifier. The EscapeCharacter option determines which
character dots, whitespace and control characters are replaced with.
Defaults to underscore ("_").

StoreRates false|true
If set to true (the default), convert counter values to rates. If set
to false counter values are stored as is, i. e. as an increasing inte-
ger number.

SeparateInstances false|true
If set to true, the plugin instance and type instance will be in their
own path component, for example "host.cpu.0.cpu.idle". If set to false
(the default), the plugin and plugin instance (and likewise the type
and type instance) are put into one component, for example
"host.cpu-0.cpu-idle".

Option value is not used when UseTags is true.

AlwaysAppendDS false|true
If set to true, append the name of the Data Source (DS) to the "metric"
identifier. If set to false (the default), this is only done when there
is more than one DS.

PreserveSeparator false|true
If set to false (the default) the "." (dot) character is replaced with
EscapeCharacter. Otherwise, if set to true, the "." (dot) character is
preserved, i.e. passed through.

Option value is not used when UseTags is true.

DropDuplicateFields false|true
If set to true, detect and remove duplicate components in Graphite met-
ric names. For example, the metric name "host.load.load.shortterm"
will be shortened to "host.load.shortterm".

UseTags false|true
If set to true, Graphite metric names will be generated as tagged se-
ries. This allows for much more flexibility than the traditional hier-
archical layout.

Example: "test.single;host=example.com;plugin=test;plugin_in-
stance=foo;type=single;type_instance=bar"

You can use Postfix option to add more tags by specifying it like
";tag1=value1;tag2=value2". Note what tagging support was added since
Graphite version 1.1.x.

If set to true, the SeparateInstances and PreserveSeparator settings
are not used.

Default value: false.

ReverseHost false|true
If set to true, the (dot separated) parts of the host field of the
value list will be rewritten in reverse order. The rewrite happens be-
fore special characters are replaced with the EscapeCharacter.

This option might be convenient if the metrics are presented with
Graphite in a DNS like tree structure (probably without replacing dots
in hostnames).

Example:
Hostname "node3.cluster1.example.com"
LoadPlugin "cpu"
LoadPlugin "write_graphite"
<Plugin "write_graphite">
<Node "graphite.example.com">
EscapeCharacter "."
ReverseHost true
</Node>
</Plugin>

result on the wire: com.example.cluster1.node3.cpu-0.cpu-idle 99.900993 1543010932

Default value: false.

Plugin "write_log"
The "write_log" plugin writes metrics as INFO log messages.

This plugin supports two output formats: Graphite and JSON.

Synopsis:

<Plugin write_log>
Format Graphite
</Plugin>

Format Format
The output format to use. Can be one of "Graphite" or "JSON".

Plugin "write_tsdb"
The "write_tsdb" plugin writes data to OpenTSDB, a scalable open-source
time series database. The plugin connects to a TSD, a masterless, no shared
state daemon that ingests metrics and stores them in HBase. The plugin uses
TCP over the "line based" protocol with a default port 4242. The data will
be sent in blocks of at most 1428 bytes to minimize the number of network
packets.

Synopsis:

<Plugin write_tsdb>
ResolveInterval 60
ResolveJitter 60
<Node "example">
Host "tsd-1.my.domain"
Port "4242"
HostTags "status=production"
</Node>
</Plugin>

The configuration consists of one or more <Node Name> blocks and global di-
rectives.

Global directives are:

ResolveInterval seconds
ResolveJitter seconds
When collectd connects to a TSDB node, it will request the hostname
from DNS. This can become a problem if the TSDB node is unavailable or
badly configured because collectd will request DNS in order to recon-
nect for every metric, which can flood your DNS. So you can cache the
last value for ResolveInterval seconds. Defaults to the Interval of
the write_tsdb plugin, e.g. 10 seconds.

You can also define a jitter, a random interval to wait in addition to
ResolveInterval. This prevents all your collectd servers to resolve the
hostname at the same time when the connection fails. Defaults to the
Interval of the write_tsdb plugin, e.g. 10 seconds.

Note: If the DNS resolution has already been successful when the socket
closes, the plugin will try to reconnect immediately with the cached
information. DNS is queried only when the socket is closed for a longer
than ResolveInterval + ResolveJitter seconds.

Inside the Node blocks, the following options are recognized:

Host Address
Hostname or address to connect to. Defaults to "localhost".

Port Service
Service name or port number to connect to. Defaults to 4242.

HostTags String
When set, HostTags is added to the end of the metric. It is intended to
be used for name=value pairs that the TSD will tag the metric with.
Dots and whitespace are not escaped in this string.

StoreRates false|true
If set to true, convert counter values to rates. If set to false (the
default) counter values are stored as is, as an increasing integer num-
ber.

AlwaysAppendDS false|true
If set the true, append the name of the Data Source (DS) to the "met-
ric" identifier. If set to false (the default), this is only done when
there is more than one DS.

Plugin "write_mongodb"
The write_mongodb plugin will send values to MongoDB, a schema-less NoSQL
database.

Synopsis:

<Plugin "write_mongodb">
<Node "default">
Host "localhost"
Port "27017"
Timeout 1000
StoreRates true
</Node>
</Plugin>

The plugin can send values to multiple instances of MongoDB by specifying
one Node block for each instance. Within the Node blocks, the following op-
tions are available:

Host Address
Hostname or address to connect to. Defaults to "localhost".

Port Service
Service name or port number to connect to. Defaults to 27017.

Timeout Milliseconds
Set the timeout for each operation on MongoDB to Timeout milliseconds.
Setting this option to zero means no timeout, which is the default.

StoreRates false|true
If set to true (the default), convert counter values to rates. If set
to false counter values are stored as is, i.e. as an increasing integer
number.

Database Database
User User
Password Password
Sets the information used when authenticating to a MongoDB database.
The fields are optional (in which case no authentication is attempted),
but if you want to use authentication all three fields must be set.

Plugin "write_prometheus"
The write_prometheus plugin implements a tiny webserver that can be scraped
using Prometheus.

Options:

Host Host
Bind to the hostname / address Host. By default, the plugin will bind
to the "any" address, i.e. accept packets sent to any of the hosts ad-
dresses.

This option is supported only for libmicrohttpd newer than 0.9.0.

Port Port
Port the embedded webserver should listen on. Defaults to 9103.

StalenessDelta Seconds
Time in seconds after which Prometheus considers a metric "stale" if it
hasn't seen any update for it. This value must match the setting in
Prometheus. It defaults to 300 seconds (5 minutes), same as
Prometheus.

Background:

Prometheus has a global setting, "StalenessDelta", which controls after
which time a metric without updates is considered "stale". This setting
effectively puts an upper limit on the interval in which metrics are
reported.

When the write_prometheus plugin encounters a metric with an interval
exceeding this limit, it will inform you, the user, and provide the
metric to Prometheus without a timestamp. That causes Prometheus to
consider the metric "fresh" each time it is scraped, with the time of
the scrape being considered the time of the update. The result is that
there appear more datapoints in Prometheus than were actually created,
but at least the metric doesn't disappear periodically.

Plugin "write_http"
This output plugin submits values to an HTTP server using POST requests and
encoding metrics with JSON or using the "PUTVAL" command described in col-
lectd-unixsock(5).

Synopsis:

<Plugin "write_http">
<Node "example">
URL "http://example.com/post-collectd"
User "collectd"
Password "weCh3ik0"
Format JSON
</Node>
</Plugin>

The plugin can send values to multiple HTTP servers by specifying one
<Node Name> block for each server. Within each Node block, the following
options are available:

URL URL
URL to which the values are submitted to. Mandatory.

User Username
Optional user name needed for authentication.

Password Password
Optional password needed for authentication.

VerifyPeer true|false
Enable or disable peer SSL certificate verification. See
<http://curl.haxx.se/docs/sslcerts.html> for details. Enabled by de-
fault.

CAPath Directory
Directory holding one or more CA certificate files. You can use this if
for some reason all the needed CA certificates aren't in the same file
and can't be pointed to using the CACert option. Requires "libcurl" to
be built against OpenSSL.

ClientKey File
File that holds the private key in PEM format to be used for certifi-
cate-based authentication.

ClientCert File
File that holds the SSL certificate to be used for certificate-based
authentication.

ClientKeyPass Password
Password required to load the private key in ClientKey.

Header Header
A HTTP header to add to the request. Multiple headers are added if
this option is specified more than once. Example:

Header "X-Custom-Header: custom_value"

Format Command|JSON|KAIROSDB
Format of the output to generate. If set to Command, will create output
that is understood by the Exec and UnixSock plugins. When set to JSON,
will create output in the JavaScript Object Notation (JSON). When set
to KAIROSDB , will create output in the KairosDB format.

Defaults to Command.

Attribute String String
Only available for the KAIROSDB output format.

Consider the two given strings to be the key and value of an additional
tag for each metric being sent out.

You can add multiple Attribute.

TTL Int
Only available for the KAIROSDB output format.

Sets the Cassandra ttl for the data points.

Please refer to <http://kairosdb.github.io/docs/build/html/restapi/Ad-
dDataPoints.html?highlight=ttl>

Prefix String
Only available for the KAIROSDB output format.

Sets the metrics prefix string. Defaults to collectd.

Metrics true|false
Controls whether metrics are POSTed to this location. Defaults to true.

Notifications false|true
Controls whether notifications are POSTed to this location. Defaults to
false.

StoreRates true|false
If set to true, convert counter values to rates. If set to false (the
default) counter values are stored as is, i.e. as an increasing integer
number.

BufferSize Bytes
Sets the send buffer size to Bytes. By increasing this buffer, less
HTTP requests will be generated, but more metrics will be batched /
metrics are cached for longer before being sent, introducing additional
delay until they are available on the server side. Bytes must be at
least 1024 and cannot exceed the size of an "int", i.e. 2 GByte. De-
faults to 4096.

LowSpeedLimit Bytes per Second
Sets the minimal transfer rate in Bytes per Second below which the con-
nection with the HTTP server will be considered too slow and aborted.
All the data submitted over this connection will probably be lost. De-
faults to 0, which means no minimum transfer rate is enforced.

Timeout Timeout
Sets the maximum time in milliseconds given for HTTP POST operations to
complete. When this limit is reached, the POST operation will be
aborted, and all the data in the current send buffer will probably be
lost. Defaults to 0, which means the connection never times out.

LogHttpError false|true
Enables printing of HTTP error code to log. Turned off by default.

<Statistics Name>
One Statistics block can be used to specify cURL statistics to be col-
lected for each request to the remote URL. See the section "cURL Sta-
tistics" above for details.

The "write_http" plugin regularly submits the collected values to the
HTTP server. How frequently this happens depends on how much data you
are collecting and the size of BufferSize. The optimal value to set
Timeout to is slightly below this interval, which you can estimate by
monitoring the network traffic between collectd and the HTTP server.

Plugin "write_influxdb_udp"
The write_influxdb_udp plugin sends data to a instance of InfluxDB using
the "Line Protocol". Each plugin is sent as a measurement with a time pre-
cision of miliseconds while plugin instance, type and type instance are
sent as tags.

<Plugin "write_influxdb_udp">
Server "influxdb.internal.tld"
StoreRates "yes"
</Plugin>

<Server Host [Port]>
The Server statement sets the server to send datagrams to.

The argument Host may be a hostname, an IPv4 address or an IPv6 ad-
dress. The optional second argument specifies a port number or a ser-
vice name. If not given, the default, 8089, is used.

StoreRates true|false
If set to true, convert absolute, counter and derive values to rates.
If set to false (the default) absolute, counter and derive values are
sent as is.

Plugin "write_kafka"
The write_kafka plugin will send values to a Kafka topic, a distributed
queue. Synopsis:

<Plugin "write_kafka">
Property "metadata.broker.list" "broker1:9092,broker2:9092"
<Topic "collectd">
Format JSON
</Topic>
</Plugin>

The following options are understood by the write_kafka plugin:

<Topic Name>
The plugin's configuration consists of one or more Topic blocks. Each
block is given a unique Name and specifies one kafka producer. Inside
the Topic block, the following per-topic options are understood:

Property String String
Configure the named property for the current topic. Properties are
forwarded to the kafka producer library librdkafka.

Key String
Use the specified string as a partitioning key for the topic. Kafka
breaks topic into partitions and guarantees that for a given topol-
ogy, the same consumer will be used for a specific key. The special
(case insensitive) string Random can be used to specify that an ar-
bitrary partition should be used.

Format Command|JSON|Graphite
Selects the format in which messages are sent to the broker. If set
to Command (the default), values are sent as "PUTVAL" commands
which are identical to the syntax used by the Exec and UnixSock
plugins.

If set to JSON, the values are encoded in the JavaScript Object No-
tation, an easy and straight forward exchange format.

If set to Graphite, values are encoded in the Graphite format,
which is "<metric> <value> <timestamp>\n".

StoreRates true|false
Determines whether or not "COUNTER", "DERIVE" and "ABSOLUTE" data
sources are converted to a rate (i.e. a "GAUGE" value). If set to
false (the default), no conversion is performed. Otherwise the con-
version is performed using the internal value cache.

Please note that currently this option is only used if the Format
option has been set to JSON.

GraphitePrefix (Format=Graphite only)
A prefix can be added in the metric name when outputting in the
Graphite format.

When GraphiteUseTags is false, prefix is added before the Host
name. Metric name will be "<prefix><host><postfix><plu-
gin><type><name>"

When GraphiteUseTags is true, prefix is added in front of series
name.

GraphitePostfix (Format=Graphite only)
A postfix can be added in the metric name when outputting in the
Graphite format.

When GraphiteUseTags is false, postfix is added after the Host
name. Metric name will be "<prefix><host><postfix><plu-
gin><type><name>"

When GraphiteUseTags is true, prefix value appended to the end of
series name (before the first ; that separates the name from the
tags).

GraphiteEscapeChar (Format=Graphite only)
Specify a character to replace dots (.) in the host part of the
metric name. In Graphite metric name, dots are used as separators
between different metric parts (host, plugin, type). Default is
"_" (Underscore).

GraphiteSeparateInstances false|true
If set to true, the plugin instance and type instance will be in
their own path component, for example "host.cpu.0.cpu.idle". If set
to false (the default), the plugin and plugin instance (and like-
wise the type and type instance) are put into one component, for
example "host.cpu-0.cpu-idle".

Option value is not used when GraphiteUseTags is true.

GraphiteAlwaysAppendDS true|false
If set to true, append the name of the Data Source (DS) to the
"metric" identifier. If set to false (the default), this is only
done when there is more than one DS.

GraphitePreserveSeparator false|true
If set to false (the default) the "." (dot) character is replaced
with GraphiteEscapeChar. Otherwise, if set to true, the "." (dot)
character is preserved, i.e. passed through.

Option value is not used when GraphiteUseTags is true.

GraphiteUseTags false|true
If set to true Graphite metric names will be generated as tagged
series.

Default value: false.

StoreRates true|false
If set to true (the default), convert counter values to rates. If
set to false counter values are stored as is, i.e. as an increasing
integer number.

This will be reflected in the "ds_type" tag: If StoreRates is en-
abled, converted values will have "rate" appended to the data
source type, e.g. "ds_type:derive:rate".

Property String String
Configure the kafka producer through properties, you almost always will
want to set metadata.broker.list to your Kafka broker list.

Plugin "write_redis"
The write_redis plugin submits values to Redis, a data structure server.

Synopsis:

<Plugin "write_redis">
<Node "example">
Host "localhost"
Port "6379"
Timeout 1000
Prefix "collectd/"
Database 1
MaxSetSize -1
MaxSetDuration -1
StoreRates true
</Node>
</Plugin>

Values are submitted to Sorted Sets, using the metric name as the key, and
the timestamp as the score. Retrieving a date range can then be done using
the "ZRANGEBYSCORE" Redis command. Additionally, all the identifiers of
these Sorted Sets are kept in a Set called "collectd/values" (or "${pre-
fix}/values" if the Prefix option was specified) and can be retrieved using
the "SMEMBERS" Redis command. You can specify the database to use with the
Database parameter (default is 0). See <http://redis.io/com-
mands#sorted_set> and <http://redis.io/commands#set> for details.

The information shown in the synopsis above is the default configuration
which is used by the plugin if no configuration is present.

The plugin can send values to multiple instances of Redis by specifying one
Node block for each instance. Within the Node blocks, the following options
are available:

Node Nodename
The Node block identifies a new Redis node, that is a new Redis in-
stance running on a specified host and port. The node name is a canoni-
cal identifier which is used as plugin instance. It is limited to
51 characters in length.

Host Hostname
The Host option is the hostname or IP-address where the Redis instance
is running on.

Timeout Milliseconds
The Timeout option sets the socket connection timeout, in milliseconds.

Prefix Prefix
Prefix used when constructing the name of the Sorted Sets and the Set
containing all metrics. Defaults to "collectd/", so metrics will have
names like "collectd/cpu-0/cpu-user". When setting this to something
different, it is recommended but not required to include a trailing
slash in Prefix.

Database Index
This index selects the redis database to use for writing operations.
Defaults to 0.

MaxSetSize Items
The MaxSetSize option limits the number of items that the Sorted Sets
can hold. Negative values for Items sets no limit, which is the default
behavior.

MaxSetDuration Seconds
The MaxSetDuration option limits the duration of items that the Sorted
Sets can hold. Negative values for Items sets no duration, which is the
default behavior.

StoreRates true|false
If set to true (the default), convert counter values to rates. If set
to false counter values are stored as is, i.e. as an increasing integer
number.

Plugin "write_riemann"
The write_riemann plugin will send values to Riemann, a powerful stream ag-
gregation and monitoring system. The plugin sends Protobuf encoded data to
Riemann using UDP packets.

Synopsis:

<Plugin "write_riemann">
<Node "example">
Host "localhost"
Port "5555"
Protocol UDP
StoreRates true
AlwaysAppendDS false
TTLFactor 2.0
</Node>
Tag "foobar"
Attribute "foo" "bar"
</Plugin>

The following options are understood by the write_riemann plugin:

<Node Name>
The plugin's configuration consists of one or more Node blocks. Each
block is given a unique Name and specifies one connection to an in-
stance of Riemann. Indise the Node block, the following per-connection
options are understood:

Host Address
Hostname or address to connect to. Defaults to "localhost".

Port Service
Service name or port number to connect to. Defaults to 5555.

Protocol UDP|TCP|TLS
Specify the protocol to use when communicating with Riemann. De-
faults to TCP.

TLSCertFile Path
When using the TLS protocol, path to a PEM certificate to present
to remote host.

TLSCAFile Path
When using the TLS protocol, path to a PEM CA certificate to use to
validate the remote hosts's identity.

TLSKeyFile Path
When using the TLS protocol, path to a PEM private key associated
with the certificate defined by TLSCertFile.

Batch true|false
If set to true and Protocol is set to TCP, events will be batched
in memory and flushed at regular intervals or when BatchMaxSize is
exceeded.

Notifications are not batched and sent as soon as possible.

When enabled, it can occur that events get processed by the Riemann
server close to or after their expiration time. Tune the TTLFactor
and BatchMaxSize settings according to the amount of values col-
lected, if this is an issue.

Defaults to true

BatchMaxSize size
Maximum payload size for a riemann packet. Defaults to 8192

BatchFlushTimeout seconds
Maximum amount of seconds to wait in between to batch flushes. No
timeout by default.

StoreRates true|false
If set to true (the default), convert counter values to rates. If
set to false counter values are stored as is, i.e. as an increasing
integer number.

This will be reflected in the "ds_type" tag: If StoreRates is en-
abled, converted values will have "rate" appended to the data
source type, e.g. "ds_type:derive:rate".

AlwaysAppendDS false|true
If set to true, append the name of the Data Source (DS) to the
"service", i.e. the field that, together with the "host" field,
uniquely identifies a metric in Riemann. If set to false (the de-
fault), this is only done when there is more than one DS.

TTLFactor Factor
Riemann events have a Time to Live (TTL) which specifies how long
each event is considered active. collectd populates this field
based on the metrics interval setting. This setting controls the
factor with which the interval is multiplied to set the TTL. The
default value is 2.0. Unless you know exactly what you're doing,
you should only increase this setting from its default value.

Notifications false|true
If set to true, create riemann events for notifications. This is
true by default. When processing thresholds from write_riemann, it
might prove useful to avoid getting notification events.

CheckThresholds false|true
If set to true, attach state to events based on thresholds defined
in the Threshold plugin. Defaults to false.

EventServicePrefix String
Add the given string as a prefix to the event service name. If
EventServicePrefix not set or set to an empty string (""), no pre-
fix will be used.

Tag String
Add the given string as an additional tag to the metric being sent to
Riemann.

Attribute String String
Consider the two given strings to be the key and value of an additional
attribute for each metric being sent out to Riemann.

Plugin "write_sensu"
The write_sensu plugin will send values to Sensu, a powerful stream aggre-
gation and monitoring system. The plugin sends JSON encoded data to a local
Sensu client using a TCP socket.

Synopsis:

<Plugin "write_sensu">
<Node "example">
Host "localhost"
Port "3030"
StoreRates true
AlwaysAppendDS false
IncludeSource false
MetricHandler "influx"
MetricHandler "default"
NotificationHandler "flapjack"
NotificationHandler "howling_monkey"
Notifications true
</Node>
Tag "foobar"
Attribute "foo" "bar"
</Plugin>

The following options are understood by the write_sensu plugin:

<Node Name>
The plugin's configuration consists of one or more Node blocks. Each
block is given a unique Name and specifies one connection to an in-
stance of Sensu. Inside the Node block, the following per-connection
options are understood:

Host Address
Hostname or address to connect to. Defaults to "localhost".

Port Service
Service name or port number to connect to. Defaults to 3030.

StoreRates true|false
If set to true (the default), convert counter values to rates. If
set to false counter values are stored as is, i.e. as an increasing
integer number.

This will be reflected in the "collectd_data_source_type" tag: If
StoreRates is enabled, converted values will have "rate" appended
to the data source type, e.g. "collectd_data_source_type:de-
rive:rate".

AlwaysAppendDS false|true
If set the true, append the name of the Data Source (DS) to the
"service", i.e. the field that, together with the "host" field,
uniquely identifies a metric in Sensu. If set to false (the de-
fault), this is only done when there is more than one DS.

Notifications false|true
If set to true, create Sensu events for notifications. This is
false by default. At least one of Notifications or Metrics should
be enabled.

Metrics false|true
If set to true, create Sensu events for metrics. This is false by
default. At least one of Notifications or Metrics should be en-
abled.

Separator String
Sets the separator for Sensu metrics name or checks. Defaults to
"/".

MetricHandler String
Add a handler that will be set when metrics are sent to Sensu. You
can add several of them, one per line. Defaults to no handler.

NotificationHandler String
Add a handler that will be set when notifications are sent to
Sensu. You can add several of them, one per line. Defaults to no
handler.

EventServicePrefix String
Add the given string as a prefix to the event service name. If
EventServicePrefix not set or set to an empty string (""), no pre-
fix will be used.

Tag String
Add the given string as an additional tag to the metric being sent to
Sensu.

Attribute String String
Consider the two given strings to be the key and value of an additional
attribute for each metric being sent out to Sensu.

IncludeSource false|true
If set to true, then the source host of the metrics/notification is
passed on to sensu using the source attribute. This may register the
host as a proxy client in sensu.

If set to false (the default), then the hostname is discarded, making
it appear as if the event originated from the connected sensu agent.

Plugin "write_stackdriver"
The "write_stackdriver" plugin writes metrics to the Google Stackdriver
Monitoring service.

This plugin supports two authentication methods: When configured, creden-
tials are read from the JSON credentials file specified with Credential-
File. Alternatively, when running on Google Compute Engine (GCE), an OAuth
token is retrieved from the metadata server and used to authenticate to
GCM.

Synopsis:

<Plugin write_stackdriver>
CredentialFile "/path/to/service_account.json"
<Resource "global">
Label "project_id" "monitored_project"
</Resource>
</Plugin>

CredentialFile file
Path to a JSON credentials file holding the credentials for a GCP ser-
vice account.

If CredentialFile is not specified, the plugin uses Application Default
Credentials. That means which credentials are used depends on the envi-
ronment:

* The environment variable "GOOGLE_APPLICATION_CREDENTIALS" is
checked. If this variable is specified it should point to a JSON
file that defines the credentials.

* The path "${HOME}/.config/gcloud/application_default_creden-
tials.json" is checked. This where credentials used by the gcloud
command line utility are stored. You can use "gcloud auth applica-
tion-default login" to create these credentials.

Please note that these credentials are often of your personal ac-
count, not a service account, and are therefore unfit to be used in
a production environment.

* When running on GCE, the built-in service account associated with
the virtual machine instance is used. See also the Email option
below.

Project Project
The Project ID or the Project Number of the Stackdriver Account. The
Project ID is a string identifying the GCP project, which you can chose
freely when creating a new project. The Project Number is a 12-digit
decimal number. You can look up both on the Developer Console.

This setting is optional. If not set, the project ID is read from the
credentials file or determined from the GCE's metadata service.

Email Email (GCE only)
Choses the GCE Service Account used for authentication.

Each GCE instance has a "default" Service Account but may also be asso-
ciated with additional Service Accounts. This is often used to restrict
the permissions of services running on the GCE instance to the required
minimum. The write_stackdriver plugin requires the
"https://www.googleapis.com/auth/monitoring" scope. When multiple Ser-
vice Accounts are available, this option selects which one is used by
write_stackdriver plugin.

Resource ResourceType
Configures the Monitored Resource to use when storing metrics. More
information on Monitored Resources and Monitored Resource Types are
available at <https://cloud.google.com/monitoring/api/resources>.

This block takes one string argument, the ResourceType. Inside the
block are one or more Label options which configure the resource la-
bels.

This block is optional. The default value depends on the runtime envi-
ronment: on GCE, the "gce_instance" resource type is used, otherwise
the "global" resource type ist used:

* On GCE, defaults to the equivalent of this config:

<Resource "gce_instance">
Label "project_id" "<project_id>"
Label "instance_id" "<instance_id>"
Label "zone" "<zone>"
</Resource>

The values for project_id, instance_id and zone are read from the
GCE metadata service.

* Elsewhere, i.e. not on GCE, defaults to the equivalent of this con-
fig:

<Resource "global">
Label "project_id" "<Project>"
</Resource>

Where Project refers to the value of the Project option or the
project ID inferred from the CredentialFile.

Url Url
URL of the Stackdriver Monitoring API. Defaults to "https://monitor-
ing.googleapis.com/v3".

Plugin "write_syslog"
The "write_syslog" plugin writes data in syslog format log messages. It
implements the basic syslog protocol, RFC 5424, extends it with con-
tent-based filtering, rich filtering capabilities, flexible configuration
options and adds features such as using TCP for transport. The plugin can
connect to a Syslog daemon, like syslog-ng and rsyslog, that will ingest
metrics, transform and ship them to the specified output. The plugin uses
TCP over the "line based" protocol with a default port 44514. The data
will be sent in blocks of at most 1428 bytes to minimize the number of net-
work packets.

Synopsis:

<Plugin write_syslog>
ResolveInterval 60
ResolveJitter 60
<Node "example">
Host "syslog-1.my.domain"
Port "44514"
Prefix "collectd"
MessageFormat "human"
HostTags ""
</Node>
</Plugin>

The configuration consists of one or more <Node Name> blocks and global di-
rectives.

Global directives are:

ResolveInterval seconds
ResolveJitter seconds
When collectd connects to a syslog node, it will request the hostname
from DNS. This can become a problem if the syslog node is unavailable
or badly configured because collectd will request DNS in order to re-
connect for every metric, which can flood your DNS. So you can cache
the last value for ResolveInterval seconds. Defaults to the Interval
of the write_syslog plugin, e.g. 10 seconds.

Inside the Node blocks, the following options are recognized:

Host Address
Hostname or address to connect to. Defaults to "localhost".

Port Service
Service name or port number to connect to. Defaults to 44514.

HostTags String
When set, HostTags is added to the end of the metric. It is intended
to be used for adding additional metadata to tag the metric with. Dots
and whitespace are not escaped in this string.

Examples:

When MessageFormat is set to "human".

["prefix1" "example1"="example1_v"]["prefix2" "example2"="example2_v"]"

When MessageFormat is set to "JSON", text should be in JSON format.
Escaping the quotation marks is required.

HostTags "\"prefix1\": {\"example1\":\"example1_v\",\"example2\":\"example2_v\"}"

MessageFormat String
MessageFormat selects the format in which messages are sent to the sys-
log deamon, human or JSON. Defaults to human.

Syslog message format:

<priority>VERSION ISOTIMESTAMP HOSTNAME APPLICATION PID MESSAGEID
STRUCTURED-DATA MSG

The difference between the message formats are in the STRUCTURED-DATA
and MSG parts.

Human format:

<166>1 ISOTIMESTAMP HOSTNAME collectd PID MESSAGEID
["collectd" "value": "v1" "plugin"="plugin_v" "plugin_instance"="plugin_instance_v"
"type_instance"="type_instance_v" "type"="type_v" "ds_name"="ds_name_v" "interval"="interval_v" ]
"host_tag_example"="host_tag_example_v" plugin_v.type_v.ds_name_v="v1"

JSON format:

<166>1 ISOTIMESTAMP HOSTNAME collectd PID MESSAGEID STRUCTURED-DATA
{
"collectd": {
"time": time_as_epoch, "interval": interval_v, "plugin": "plugin_v",
"plugin_instance": "plugin_instance_v", "type":"type_v",
"type_instance": "type_instance_v", "plugin_v": {"type_v": v1}
} , "host":"host_v", "host_tag_example": "host_tag_example_v"
}

StoreRates false|true
If set to true, convert counter values to rates. If set to false (the
default) counter values are stored as is, as an increasing integer num-
ber.

AlwaysAppendDS false|true
If set to true, append the name of the Data Source (DS) to the "metric"
identifier. If set to false (the default), this is only done when there
is more than one DS.

Prefix String
When set, Prefix is added to all metrics names as a prefix. It is in-
tended in case you want to be able to define the source of the specific
metric. Dots and whitespace are not escaped in this string.

Plugin "xencpu"
This plugin collects metrics of hardware CPU load for machine running Xen
hypervisor. Load is calculated from 'idle time' value, provided by Xen.
Result is reported using the "percent" type, for each CPU (core).

This plugin doesn't have any options (yet).

Plugin "zookeeper"
The zookeeper plugin will collect statistics from a Zookeeper server using
the mntr command. It requires Zookeeper 3.4.0+ and access to the client
port.

Synopsis:

Host Address
Hostname or address to connect to. Defaults to "localhost".

Port Service
Service name or port number to connect to. Defaults to 2181.

THRESHOLD CONFIGURATION
Starting with version 4.3.0 collectd has support for monitoring. By that we
mean that the values are not only stored or sent somewhere, but that they
are judged and, if a problem is recognized, acted upon. The only action
collectd takes itself is to generate and dispatch a "notification". Plugins
can register to receive notifications and perform appropriate further ac-
tions.

Since systems and what you expect them to do differ a lot, you can config-
ure thresholds for your values freely. This gives you a lot of flexibility
but also a lot of responsibility.

Every time a value is out of range a notification is dispatched. This means
that the idle percentage of your CPU needs to be less then the configured
threshold only once for a notification to be generated. There's no such
thing as a moving average or similar - at least not now.

Also, all values that match a threshold are considered to be relevant or
"interesting". As a consequence collectd will issue a notification if they
are not received for Timeout iterations. The Timeout configuration option
is explained in section "GLOBAL OPTIONS". If, for example, Timeout is set
to "2" (the default) and some hosts sends it's CPU statistics to the server
every 60 seconds, a notification will be dispatched after about 120 sec-
onds. It may take a little longer because the timeout is checked only once
each Interval on the server.

When a value comes within range again or is received after it was missing,
an "OKAY-notification" is dispatched.

Here is a configuration example to get you started. Read below for more in-
formation.

<Plugin threshold>
<Type "foo">
WarningMin 0.00
WarningMax 1000.00
FailureMin 0.00
FailureMax 1200.00
Invert false
Instance "bar"
</Type>

<Plugin "interface">
Instance "eth0"
<Type "if_octets">
FailureMax 10000000
DataSource "rx"
</Type>
</Plugin>

<Host "hostname">
<Type "cpu">
Instance "idle"
FailureMin 10
</Type>

<Plugin "memory">
<Type "memory">
Instance "cached"
WarningMin 100000000
</Type>
</Plugin>
</Host>
</Plugin>

There are basically two types of configuration statements: The "Host",
"Plugin", and "Type" blocks select the value for which a threshold should
be configured. The "Plugin" and "Type" blocks may be specified further us-
ing the "Instance" option. You can combine the block by nesting the blocks,
though they must be nested in the above order, i. e. "Host" may contain ei-
ther "Plugin" and "Type" blocks, "Plugin" may only contain "Type" blocks
and "Type" may not contain other blocks. If multiple blocks apply to the
same value the most specific block is used.

The other statements specify the threshold to configure. They must be in-
cluded in a "Type" block. Currently the following statements are recog-
nized:

FailureMax Value
WarningMax Value
Sets the upper bound of acceptable values. If unset defaults to posi-
tive infinity. If a value is greater than FailureMax a FAILURE notifi-
cation will be created. If the value is greater than WarningMax but
less than (or equal to) FailureMax a WARNING notification will be cre-
ated.

FailureMin Value
WarningMin Value
Sets the lower bound of acceptable values. If unset defaults to nega-
tive infinity. If a value is less than FailureMin a FAILURE notifica-
tion will be created. If the value is less than WarningMin but greater
than (or equal to) FailureMin a WARNING notification will be created.

DataSource DSName
Some data sets have more than one "data source". Interesting examples
are the "if_octets" data set, which has received ("rx") and sent ("tx")
bytes and the "disk_ops" data set, which holds "read" and "write" oper-
ations. The system load data set, "load", even has three data sources:
"shortterm", "midterm", and "longterm".

Normally, all data sources are checked against a configured threshold.
If this is undesirable, or if you want to specify different limits for
each data source, you can use the DataSource option to have a threshold
apply only to one data source.

Invert true|false
If set to true the range of acceptable values is inverted, i. e. val-
ues between FailureMin and FailureMax (WarningMin and WarningMax) are
not okay. Defaults to false.

Persist true|false
Sets how often notifications are generated. If set to true one notifi-
cation will be generated for each value that is out of the acceptable
range. If set to false (the default) then a notification is only gener-
ated if a value is out of range but the previous value was okay.

This applies to missing values, too: If set to true a notification
about a missing value is generated once every Interval seconds. If set
to false only one such notification is generated until the value ap-
pears again.

Percentage true|false
If set to true, the minimum and maximum values given are interpreted as
percentage value, relative to the other data sources. This is helpful
for example for the "df" type, where you may want to issue a warning
when less than 5 % of the total space is available. Defaults to false.

Hits Number
Delay creating the notification until the threshold has been passed
Number times. When a notification has been generated, or when a subse-
quent value is inside the threshold, the counter is reset. If, for ex-
ample, a value is collected once every 10 seconds and Hits is set to 3,
a notification will be dispatched at most once every 30 seconds.

This is useful when short bursts are not a problem. If, for example,
100% CPU usage for up to a minute is normal (and data is collected
every 10 seconds), you could set Hits to 6 to account for this.

Hysteresis Number
When set to non-zero, a hysteresis value is applied when checking mini-
mum and maximum bounds. This is useful for values that increase slowly
and fluctuate a bit while doing so. When these values come close to the
threshold, they may "flap", i.e. switch between failure / warning case
and okay case repeatedly.

If, for example, the threshold is configures as

WarningMax 100.0
Hysteresis 1.0

then a Warning notification is created when the value exceeds 101 and
the corresponding Okay notification is only created once the value
falls below 99, thus avoiding the "flapping".

FILTER CONFIGURATION
Starting with collectd 4.6 there is a powerful filtering infrastructure im-
plemented in the daemon. The concept has mostly been copied from ip_tables,
the packet filter infrastructure for Linux. We'll use a similar terminol-
ogy, so that users that are familiar with iptables feel right at home.

Terminology
The following are the terms used in the remainder of the filter configura-
tion documentation. For an ASCII-art schema of the mechanism, see "General
structure" below.

Match
A match is a criteria to select specific values. Examples are, of
course, the name of the value or it's current value.

Matches are implemented in plugins which you have to load prior to us-
ing the match. The name of such plugins starts with the "match_" pre-
fix.

Target
A target is some action that is to be performed with data. Such actions
could, for example, be to change part of the value's identifier or to
ignore the value completely.

Some of these targets are built into the daemon, see "Built-in targets"
below. Other targets are implemented in plugins which you have to load
prior to using the target. The name of such plugins starts with the
"target_" prefix.

RuleThe combination of any number of matches and at least one target is
called a rule. The target actions will be performed for all values for
which all matches apply. If the rule does not have any matches associ-
ated with it, the target action will be performed for all values.

Chain
A chain is a list of rules and possibly default targets. The rules are
tried in order and if one matches, the associated target will be
called. If a value is handled by a rule, it depends on the target
whether or not any subsequent rules are considered or if traversal of
the chain is aborted, see "Flow control" below. After all rules have
been checked, the default targets will be executed.

General structure
The following shows the resulting structure:

+---------+
! Chain !
+---------+
!
V
+---------+ +---------+ +---------+ +---------+
! Rule !->! Match !->! Match !->! Target !
+---------+ +---------+ +---------+ +---------+
!
V
+---------+ +---------+ +---------+
! Rule !->! Target !->! Target !
+---------+ +---------+ +---------+
!
V
:
:
!
V
+---------+ +---------+ +---------+
! Rule !->! Match !->! Target !
+---------+ +---------+ +---------+
!
V
+---------+
! Default !
! Target !
+---------+

Flow control
There are four ways to control which way a value takes through the filter
mechanism:

jumpThe built-in jump target can be used to "call" another chain, i. e.
process the value with another chain. When the called chain finishes,
usually the next target or rule after the jump is executed.

stopThe stop condition, signaled for example by the built-in target stop,
causes all processing of the value to be stopped immediately.

return
Causes processing in the current chain to be aborted, but processing of
the value generally will continue. This means that if the chain was
called via Jump, the next target or rule after the jump will be exe-
cuted. If the chain was not called by another chain, control will be
returned to the daemon and it may pass the value to another chain.

continue
Most targets will signal the continue condition, meaning that process-
ing should continue normally. There is no special built-in target for
this condition.

Synopsis
The configuration reflects this structure directly:

PostCacheChain "PostCache"
<Chain "PostCache">
<Rule "ignore_mysql_show">
<Match "regex">
Plugin "^mysql$"
Type "^mysql_command$"
TypeInstance "^show_"
</Match>
<Target "stop">
</Target>
</Rule>
<Target "write">
Plugin "rrdtool"
</Target>
</Chain>

The above configuration example will ignore all values where the plugin
field is "mysql", the type is "mysql_command" and the type instance begins
with "show_". All other values will be sent to the "rrdtool" write plugin
via the default target of the chain. Since this chain is run after the
value has been added to the cache, the MySQL "show_*" command statistics
will be available via the "unixsock" plugin.

List of configuration options
PreCacheChain ChainName
PostCacheChain ChainName
Configure the name of the "pre-cache chain" and the "post-cache chain".
The argument is the name of a chain that should be executed before
and/or after the values have been added to the cache.

To understand the implications, it's important you know what is going
on inside collectd. The following diagram shows how values are passed
from the read-plugins to the write-plugins:

+---------------+
! Read-Plugin !
+-------+-------+
!
+ - - - - V - - - - +
: +---------------+ :
: ! Pre-Cache ! :
: ! Chain ! :
: +-------+-------+ :
: ! :
: V :
: +-------+-------+ : +---------------+
: ! Cache !--->! Value Cache !
: ! insert ! : +---+---+-------+
: +-------+-------+ : ! !
: ! ,------------' !
: V V : V
: +-------+---+---+ : +-------+-------+
: ! Post-Cache +--->! Write-Plugins !
: ! Chain ! : +---------------+
: +---------------+ :
: :
: dispatch values :
+ - - - - - - - - - +

After the values are passed from the "read" plugins to the dispatch
functions, the pre-cache chain is run first. The values are added to
the internal cache afterwards. The post-cache chain is run after the
values have been added to the cache. So why is it such a huge deal if
chains are run before or after the values have been added to this
cache?

Targets that change the identifier of a value list should be executed
before the values are added to the cache, so that the name in the cache
matches the name that is used in the "write" plugins. The "unixsock"
plugin, too, uses this cache to receive a list of all available values.
If you change the identifier after the value list has been added to the
cache, this may easily lead to confusion, but it's not forbidden of
course.

The cache is also used to convert counter values to rates. These rates
are, for example, used by the "value" match (see below). If you use the
rate stored in the cache before the new value is added, you will use
the old, previous rate. Write plugins may use this rate, too, see the
"csv" plugin, for example. The "unixsock" plugin uses these rates too,
to implement the "GETVAL" command.

Last but not last, the stop target makes a difference: If the pre-cache
chain returns the stop condition, the value will not be added to the
cache and the post-cache chain will not be run.

Chain Name
Adds a new chain with a certain name. This name can be used to refer to
a specific chain, for example to jump to it.

Within the Chain block, there can be Rule blocks and Target blocks.

Rule [Name]
Adds a new rule to the current chain. The name of the rule is optional
and currently has no meaning for the daemon.

Within the Rule block, there may be any number of Match blocks and
there must be at least one Target block.

Match Name
Adds a match to a Rule block. The name specifies what kind of match
should be performed. Available matches depend on the plugins that have
been loaded.

The arguments inside the Match block are passed to the plugin imple-
menting the match, so which arguments are valid here depends on the
plugin being used. If you do not need any to pass any arguments to a
match, you can use the shorter syntax:

Match "foobar"

Which is equivalent to:

Target Name
Add a target to a rule or a default target to a chain. The name speci-
fies what kind of target is to be added. Which targets are available
depends on the plugins being loaded.

The arguments inside the Target block are passed to the plugin imple-
menting the target, so which arguments are valid here depends on the
plugin being used. If you do not need any to pass any arguments to a
target, you can use the shorter syntax:

Target "stop"

This is the same as writing:

Built-in targets
The following targets are built into the core daemon and therefore need no
plugins to be loaded:

return
Signals the "return" condition, see the "Flow control" section above.
This causes the current chain to stop processing the value and returns
control to the calling chain. The calling chain will continue process-
ing targets and rules just after the jump target (see below). This is
very similar to the RETURN target of iptables, see iptables(8).

This target does not have any options.

Example:

Target "return"

stopSignals the "stop" condition, see the "Flow control" section above.
This causes processing of the value to be aborted immediately. This is
similar to the DROP target of iptables, see iptables(8).

This target does not have any options.

Example:

Target "stop"

write
Sends the value to "write" plugins.

Available options:

Plugin Name
Name of the write plugin to which the data should be sent. This op-
tion may be given multiple times to send the data to more than one
write plugin. If the plugin supports multiple instances, the plu-
gin's instance(s) must also be specified.

If no plugin is explicitly specified, the values will be sent to all
available write plugins.

Single-instance plugin example:

<Target "write">
Plugin "rrdtool"
</Target>

Multi-instance plugin example:

<Plugin "write_graphite">
<Node "foo">
...
</Node>
<Node "bar">
...
</Node>
</Plugin>
...
<Target "write">
Plugin "write_graphite/foo"
</Target>

jumpStarts processing the rules of another chain, see "Flow control" above.
If the end of that chain is reached, or a stop condition is encoun-
tered, processing will continue right after the jump target, i. e. with
the next target or the next rule. This is similar to the -j command
line option of iptables, see iptables(8).

Available options:

Chain Name
Jumps to the chain Name. This argument is required and may appear
only once.

Example:

<Target "jump">
Chain "foobar"
</Target>

Available matches
regex
Matches a value using regular expressions.

Available options:

Host Regex
Plugin Regex
PluginInstance Regex
Type Regex
TypeInstance Regex
MetaData String Regex
Match values where the given regular expressions match the various
fields of the identifier of a value. If multiple regular expres-
sions are given, all regexen must match for a value to match.

Invert false|true
When set to true, the result of the match is inverted, i.e. all
value lists where all regular expressions apply are not matched,
all other value lists are matched. Defaults to false.

Example:

<Match "regex">
Host "customer[0-9]+"
Plugin "^foobar$"
</Match>

timediff
Matches values that have a time which differs from the time on the
server.

This match is mainly intended for servers that receive values over the
"network" plugin and write them to disk using the "rrdtool" plugin.
RRDtool is very sensitive to the timestamp used when updating the RRD
files. In particular, the time must be ever increasing. If a misbehav-
ing client sends one packet with a timestamp far in the future, all
further packets with a correct time will be ignored because of that one
packet. What's worse, such corrupted RRD files are hard to fix.

This match lets one match all values outside a specified time range
(relative to the server's time), so you can use the stop target (see
below) to ignore the value, for example.

Available options:

Future Seconds
Matches all values that are ahead of the server's time by Seconds
or more seconds. Set to zero for no limit. Either Future or Past
must be non-zero.

Past Seconds
Matches all values that are behind of the server's time by Seconds
or more seconds. Set to zero for no limit. Either Future or Past
must be non-zero.

Example:

<Match "timediff">
Future 300
Past 3600
</Match>

This example matches all values that are five minutes or more ahead of
the server or one hour (or more) lagging behind.

value
Matches the actual value of data sources against given minimum / maxi-
mum values. If a data-set consists of more than one data-source, all
data-sources must match the specified ranges for a positive match.

Available options:

Min Value
Sets the smallest value which still results in a match. If unset,
behaves like negative infinity.

Max Value
Sets the largest value which still results in a match. If unset,
behaves like positive infinity.

Invert true|false
Inverts the selection. If the Min and Max settings result in a
match, no-match is returned and vice versa. Please note that the
Invert setting only effects how Min and Max are applied to a spe-
cific value. Especially the DataSource and Satisfy settings (see
below) are not inverted.

DataSource DSName [DSName ...]
Select one or more of the data sources. If no data source is con-
figured, all data sources will be checked. If the type handled by
the match does not have a data source of the specified name(s),
this will always result in no match (independent of the Invert set-
ting).

Satisfy Any|All
Specifies how checking with several data sources is performed. If
set to Any, the match succeeds if one of the data sources is in the
configured range. If set to All the match only succeeds if all data
sources are within the configured range. Default is All.

Usually All is used for positive matches, Any is used for negative
matches. This means that with All you usually check that all values
are in a "good" range, while with Any you check if any value is
within a "bad" range (or outside the "good" range).

Either Min or Max, but not both, may be unset.

Example:

# Match all values smaller than or equal to 100. Matches only if all data
# sources are below 100.
<Match "value">
Max 100
Satisfy "All"
</Match>

# Match if the value of any data source is outside the range of 0 - 100.
<Match "value">
Min 0
Max 100
Invert true
Satisfy "Any"
</Match>

empty_counter
Matches all values with one or more data sources of type COUNTER and
where all counter values are zero. These counters usually never in-
creased since they started existing (and are therefore uninteresting),
or got reset recently or overflowed and you had really, really bad
luck.

Please keep in mind that ignoring such counters can result in confusing
behavior: Counters which hardly ever increase will be zero for long pe-
riods of time. If the counter is reset for some reason (machine or ser-
vice restarted, usually), the graph will be empty (NAN) for a long
time. People may not understand why.

hashed
Calculates a hash value of the host name and matches values according
to that hash value. This makes it possible to divide all hosts into
groups and match only values that are in a specific group. The intended
use is in load balancing, where you want to handle only part of all
data and leave the rest for other servers.

The hashing function used tries to distribute the hosts evenly. First,
it calculates a 32 bit hash value using the characters of the hostname:

hash_value = 0;
for (i = 0; host[i] != 0; i++)
hash_value = (hash_value * 251) + host[i];

The constant 251 is a prime number which is supposed to make this hash
value more random. The code then checks the group for this host accord-
ing to the Total and Match arguments:

if ((hash_value % Total) == Match)
matches;
else
does not match;

Please note that when you set Total to two (i. e. you have only two
groups), then the least significant bit of the hash value will be the
XOR of all least significant bits in the host name. One consequence is
that when you have two hosts, "server0.example.com" and "server1.exam-
ple.com", where the host name differs in one digit only and the digits
differ by one, those hosts will never end up in the same group.

Available options:

Match Match Total
Divide the data into Total groups and match all hosts in group
Match as described above. The groups are numbered from zero, i. e.
Match must be smaller than Total. Total must be at least one, al-
though only values greater than one really do make any sense.

You can repeat this option to match multiple groups, for example:

Match 3 7
Match 5 7

The above config will divide the data into seven groups and match
groups three and five. One use would be to keep every value on two
hosts so that if one fails the missing data can later be recon-
structed from the second host.

Example:

# Operate on the pre-cache chain, so that ignored values are not even in the
# global cache.
<Chain "PreCache">
<Rule>
<Match "hashed">
# Divide all received hosts in seven groups and accept all hosts in
# group three.
Match 3 7
</Match>
# If matched: Return and continue.
Target "return"
</Rule>
# If not matched: Return and stop.
Target "stop"
</Chain>

Available targets
notification
Creates and dispatches a notification.

Available options:

Message String
This required option sets the message of the notification. The fol-
lowing placeholders will be replaced by an appropriate value:

%{host}
%{plugin}
%{plugin_instance}
%{type}
%{type_instance}
These placeholders are replaced by the identifier field of the
same name.

%{ds:name}
These placeholders are replaced by a (hopefully) human readable
representation of the current rate of this data source. If you
changed the instance name (using the set or replace targets,
see below), it may not be possible to convert counter values to
rates.

Please note that these placeholders are case sensitive!

Severity "FAILURE"|"WARNING"|"OKAY"
Sets the severity of the message. If omitted, the severity "WARN-
ING" is used.

Example:

<Target "notification">
Message "Oops, the %{type_instance} temperature is currently %{ds:value}!"
Severity "WARNING"
</Target>

replace
Replaces parts of the identifier using regular expressions.

Available options:

Host Regex Replacement
Plugin Regex Replacement
PluginInstance Regex Replacement
TypeInstance Regex Replacement
MetaData String Regex Replacement
DeleteMetaData String Regex
Match the appropriate field with the given regular expression
Regex. If the regular expression matches, that part that matches is
replaced with Replacement. If multiple places of the input buffer
match a given regular expression, only the first occurrence will be
replaced.

You can specify each option multiple times to use multiple regular
expressions one after another.

Example:

<Target "replace">
# Replace "example.net" with "example.com"
Host "\\<example.net\\>" "example.com"

# Strip "www." from hostnames
Host "\\<www\\." ""
</Target>

set Sets part of the identifier of a value to a given string.

Available options:

Host String
Plugin String
PluginInstance String
TypeInstance String
MetaData String String
Set the appropriate field to the given string. The strings for plu-
gin instance, type instance, and meta data may be empty, the
strings for host and plugin may not be empty. It's currently not
possible to set the type of a value this way.

The following placeholders will be replaced by an appropriate
value:

%{host}
%{plugin}
%{plugin_instance}
%{type}
%{type_instance}
These placeholders are replaced by the identifier field of the
same name.

%{meta:name}
These placeholders are replaced by the meta data value with the
given name.

Please note that these placeholders are case sensitive!

DeleteMetaData String
Delete the named meta data field.

Example:

<Target "set">
PluginInstance "coretemp"
TypeInstance "core3"
</Target>

Backwards compatibility
If you use collectd with an old configuration, i. e. one without a Chain
block, it will behave as it used to. This is equivalent to the following
configuration:

<Chain "PostCache">
Target "write"
</Chain>

If you specify a PostCacheChain, the write target will not be added any-
where and you will have to make sure that it is called where appropriate.
We suggest to add the above snippet as default target to your "PostCache"
chain.

Examples
Ignore all values, where the hostname does not contain a dot, i. e. can't
be an FQDN.

<Chain "PreCache">
<Rule "no_fqdn">
<Match "regex">
Host "^[^\.]*$"
</Match>
Target "stop"
</Rule>
Target "write"
</Chain>

IGNORELISTS
Ignorelists are a generic framework to either ignore some metrics or report
specific metrics only. Plugins usually provide one or more options to spec-
ify the items (mounts points, devices, ...) and the boolean option "Ignore-
Selected".

Select String
Selects the item String. This option often has a plugin specific name,
e.g. Sensor in the "sensors" plugin. It is also plugin specific what
this string is compared to. For example, the "df" plugin's MountPoint
compares it to a mount point and the "sensors" plugin's Sensor compares
it to a sensor name.

By default, this option is doing a case-sensitive full-string match.
The following config will match "foo", but not "Foo":

Select "foo"

If String starts and ends with "/" (a slash), the string is compiled as
a regular expression. For example, so match all item starting with
"foo", use could use the following syntax:

Select "/^foo/"

The regular expression is not anchored, i.e. the following config will
match "foobar", "barfoo" and "AfooZ":

Select "/foo/"

The Select option may be repeated to select multiple items.

IgnoreSelected true|false
If set to true, matching metrics are ignored and all other metrics are
collected. If set to false, matching metrics are collected and all
other metrics are ignored.

SEE ALSO
collectd(1), collectd-exec(5), collectd-perl(5), collectd-unixsock(5),
types.db(5), hddtemp(8), iptables(8), kstat(3KSTAT), mbmon(1), psql(1),
regex(7), rrdtool(1), sensors(1)

AUTHOR
Florian Forster <octo@collectd.org>

5.12.0.git 2026-08-04 COLLECTD.CONF(5)

Want to link to this manual page? Use this URL:
<https://man.freebsd.org/cgi/man.cgi?query=collectd.conf&sektion=5&manpath=FreeBSD+Ports+15.1.quarterly>

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