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ovs-vswitchd.conf.db(5)        Open vSwitch Manual	 ovs-vswitchd.conf.db(5)

NAME
     ovs-vswitchd.conf.db - Open_vSwitch database schema

     A	database  with	this schema holds the configuration for one Open vSwitch
     daemon. The top-level configuration for the daemon is the Open_vSwitch  ta-
     ble,  which  must have exactly one record. Records in other tables are sig-
     nificant only when they can be reached  directly  or  indirectly  from  the
     Open_vSwitch  table.  Records  that are not reachable from the Open_vSwitch
     table are automatically deleted from the database, except for records in  a
     few distinguished ``root set'' tables.

   Common Columns
     Most  tables  contain  two  special  columns, named other_config and exter-
     nal_ids. These columns have the same form and purpose each place that  they
     appear, so we describe them here to save space later.

	    other_config: map of string-string pairs
		   Key-value  pairs  for  configuring rarely used features. Sup-
		   ported keys, along with the forms taken by their values,  are
		   documented individually for each table.

		   A few tables do not have other_config columns because no key-
		   value pairs have yet been defined for them.

	    external_ids: map of string-string pairs
		   Key-value pairs for use by external frameworks that integrate
		   with Open vSwitch, rather than by Open vSwitch itself. System
		   integrators	should	either	use the Open vSwitch development
		   mailing list to coordinate on common  key-value  definitions,
		   or  choose  key  names  that are likely to be unique. In some
		   cases, where key-value  pairs  have	been  defined  that  are
		   likely  to be widely useful, they are documented individually
		   for each table.

TABLE SUMMARY
     The following list summarizes the purpose of each	of  the  tables  in  the
     Open_vSwitch  database.   Each table is described in more detail on a later
     page.

     Table     Purpose
     Open_vSwitch
	       Open vSwitch configuration.
     Bridge    Bridge configuration.
     Port      Port configuration.
     Interface
	       One physical network device in a Port.
     Flow_Table
	       OpenFlow table configuration
     QoS       Quality of Service configuration
     Queue     QoS output queue.
     Mirror    Port mirroring.
     Controller
	       OpenFlow controller configuration.
     Manager   OVSDB management connection.
     NetFlow   NetFlow configuration.
     Datapath  Datapath configuration.
     CT_Zone   CT_Zone configuration.
     CT_Timeout_Policy
	       CT_Timeout_Policy configuration.
     SSL       SSL configuration.
     sFlow     sFlow configuration.
     IPFIX     IPFIX configuration.
     Flow_Sample_Collector_Set
	       Flow_Sample_Collector_Set configuration.
     AutoAttach
	       AutoAttach configuration.

Open_vSwitch TABLE
     Configuration for an Open vSwitch daemon. There must be exactly one  record
     in the Open_vSwitch table.

   Summary:
     Configuration:
       datapaths		   map of string-Datapath pairs
       bridges			   set of Bridges
       ssl			   optional SSL
       external_ids : system-id    optional string
       external_ids : xs-system-uuid
				   optional string
       external_ids : hostname	   optional string
       external_ids : rundir	   optional string
       other_config : stats-update-interval
				   optional  string,  containing  an integer, at
				   least 5,000
       other_config : flow-restore-wait
				   optional string, either true or false
       other_config : flow-limit   optional string, containing	an  integer,  at
				   least 0
       other_config : max-idle	   optional  string,  containing  an integer, at
				   least 500
       other_config : max-revalidator
				   optional string, containing	an  integer,  at
				   least 100
       other_config : min-revalidate-pps
				   optional  string,  containing  an integer, at
				   least 1
       other_config : offloaded-stats-delay
				   optional string, containing	an  integer,  at
				   least 0
       other_config : hw-offload   optional string, either true or false
       other_config : n-offload-threads
				   optional  string,  containing  an integer, in
				   range 1 to 10
       other_config : tc-policy    optional string, one  of  none,  skip_hw,  or
				   skip_sw
       other_config : dpdk-init    optional string, one of false, true, or try
       other_config : dpdk-lcore-mask
				   optional  string,  containing  an integer, at
				   least 1
       other_config : pmd-cpu-mask
				   optional string
       other_config : dpdk-alloc-mem
				   optional string, containing	an  integer,  at
				   least 0
       other_config : dpdk-socket-mem
				   optional string
       other_config : dpdk-socket-limit
				   optional string
       other_config : dpdk-hugepage-dir
				   optional string
       other_config : dpdk-extra   optional string
       other_config : vhost-sock-dir
				   optional string
       other_config : vhost-iommu-support
				   optional string, either true or false
       other_config : vhost-postcopy-support
				   optional string, either true or false
       other_config : per-port-memory
				   optional string, either true or false
       other_config : tx-flush-interval
				   optional  string,  containing  an integer, in
				   range 0 to 1,000,000
       other_config : pmd-perf-metrics
				   optional string, either true or false
       other_config : smc-enable   optional string, either true or false
       other_config : pmd-rxq-assign
				   optional string, one  of  cycles,  group,  or
				   roundrobin
       other_config : pmd-rxq-isolate
				   optional string, either true or false
       other_config : n-handler-threads
				   optional  string,  containing  an integer, at
				   least 1
       other_config : n-revalidator-threads
				   optional string, containing	an  integer,  at
				   least 1
       other_config : emc-insert-inv-prob
				   optional  string,  containing  an integer, in
				   range 0 to 4,294,967,295
       other_config : vlan-limit   optional string, containing	an  integer,  at
				   least 0
       other_config : bundle-idle-timeout
				   optional  string,  containing  an integer, at
				   least 1
       other_config : offload-rebalance
				   optional string, either true or false
       other_config : pmd-auto-lb
				   optional string, either true or false
       other_config : pmd-auto-lb-rebal-interval
				   optional string, containing	an  integer,  in
				   range 0 to 20,000
       other_config : pmd-auto-lb-load-threshold
				   optional  string,  containing  an integer, in
				   range 0 to 100
       other_config : pmd-auto-lb-improvement-threshold
				   optional string, containing	an  integer,  in
				   range 0 to 100
       other_config : userspace-tso-enable
				   optional string, either true or false
     Status:
       next_cfg 		   integer
       cur_cfg			   integer
       dpdk_initialized 	   boolean
       Statistics:
	  other_config : enable-statistics
				   optional string, either true or false
	  statistics : cpu	   optional  string,  containing  an integer, at
				   least 1
	  statistics : load_average
				   optional string
	  statistics : memory	   optional string
	  statistics : process_NAME
				   optional string
	  statistics : file_systems
				   optional string
     Version Reporting:
       ovs_version		   optional string
       db_version		   optional string
       system_type		   optional string
       system_version		   optional string
       dpdk_version		   optional string
     Capabilities:
       datapath_types		   set of strings
       iface_types		   set of strings
     Database Configuration:
       manager_options		   set of Managers
     IPsec:
       other_config : private_key
				   optional string
       other_config : certificate
				   optional string
       other_config : ca_cert	   optional string
       Plaintext Tunnel Policy:
	  other_config : ipsec_skb_mark
				   optional string
     Common Columns:
       other_config		   map of string-string pairs
       external_ids		   map of string-string pairs

   Details:
   Configuration:

     datapaths: map of string-Datapath pairs
	    Map of datapath types to datapaths. The datapath_type column of  the
	    Bridge  table  is  used as a key for this map. The value points to a
	    row in the Datapath table.

     bridges: set of Bridges
	    Set of bridges managed by the daemon.

     ssl: optional SSL
	    SSL used globally by the daemon.

     external_ids : system-id: optional string
	    A unique identifier for the Open vSwitch's physical host.  The  form
	    of	the  identifier  depends  on  the  type of the host. On a Citrix
	    XenServer, this will likely be the same  as  external_ids:xs-system-
	    uuid.

     external_ids : xs-system-uuid: optional string
	    The  Citrix XenServer universally unique identifier for the physical
	    host as displayed by xe host-list.

     external_ids : hostname: optional string
	    The hostname for the host running Open  vSwitch.  This  is	a  fully
	    qualified domain name since version 2.6.2.

     external_ids : rundir: optional string
	    In Open vSwitch 2.8 and later, the run directory of the running Open
	    vSwitch  daemon.  This  directory  is used for runtime state such as
	    control and management sockets.  The  value  of  other_config:vhost-
	    sock-dir is relative to this directory.

     other_config : stats-update-interval: optional string, containing an inte-
     ger, at least 5,000
	    Interval  for  updating statistics to the database, in milliseconds.
	    This option will affect the update of the statistics column  in  the
	    following tables: Port, Interface , Mirror.

	    Default value is 5000 ms.

	    Getting statistics more frequently can be achieved via OpenFlow.

     other_config : flow-restore-wait: optional string, either true or false
	    When  ovs-vswitchd	starts up, it has an empty flow table and there-
	    fore it handles all arriving packets in its default fashion  accord-
	    ing  to  its  configuration,  by dropping them or sending them to an
	    OpenFlow controller or switching them as a standalone  switch.  This
	    behavior  is  ordinarily  desirable.  However,  if	ovs-vswitchd  is
	    restarting as part of a ``hot-upgrade,'' then this leads to a  rela-
	    tively long period during which packets are mishandled.

	    This  option  allows  for improvement. When ovs-vswitchd starts with
	    this value set as true, it will neither flush or  expire  previously
	    set  datapath  flows  nor will it send and receive any packets to or
	    from  the  datapath.  When	this  value  is  later	set  to   false,
	    ovs-vswitchd  will start receiving packets from the datapath and re-
	    setup the flows.

	    Additionally, ovs-vswitchd is  prevented  from  connecting	to  con-
	    trollers  when  this value is set to true. This prevents controllers
	    from making changes to the flow table in the middle of flow restora-
	    tion, which could result in undesirable  intermediate  states.  Once
	    this value has been set to false and the desired flow state has been
	    restored,  ovs-vswitchd will be able to reconnect to controllers and
	    process any new flow table modifications.

	    Thus,  with  this  option,	the  procedure	for  a	hot-upgrade   of
	    ovs-vswitchd becomes roughly the following:

	    1.	Stop ovs-vswitchd.

	    2.	Set other_config:flow-restore-wait to true.

	    3.	Start ovs-vswitchd.

	    4.	Use  ovs-ofctl	(or some other program, such as an OpenFlow con-
		troller) to restore the  OpenFlow  flow  table	to  the  desired
		state.

	    5.	Set  other_config:flow-restore-wait  to  false (or remove it en-
		tirely from the database).

	    The ovs-ctl's ``restart'' and  ``force-reload-kmod''  functions  use
	    the above config option during hot upgrades.

     other_config : flow-limit: optional string, containing an integer, at least
     0
	    The  maximum number of flows allowed in the datapath flow table. In-
	    ternally OVS will choose a flow limit which  will  likely  be  lower
	    than  this	number,  based on real time network conditions. Tweaking
	    this value is discouraged unless you know exactly what you're doing.

	    The default is 200000.

     other_config : max-idle: optional string, containing an integer, at least
     500
	    The maximum time (in ms) that idle flows will remain cached  in  the
	    datapath.  Internally  OVS	will check the validity and activity for
	    datapath flows regularly and may expire flows quicker than this num-
	    ber, based on real time network conditions. Tweaking this  value  is
	    discouraged unless you know exactly what you're doing.

	    The default is 10000.

     other_config : max-revalidator: optional string, containing an integer, at
     least 100
	    The  maximum  time (in ms) that revalidator threads will wait before
	    executing flow revalidation.  Note	that  this  is	maximum  allowed
	    value.  Actual  timeout  used by OVS is minimum of max-idle and max-
	    revalidator values. Tweaking this value is	discouraged  unless  you
	    know exactly what you're doing.

	    The default is 500.

     other_config : min-revalidate-pps: optional string, containing an integer,
     at least 1
	    Set  minimum pps that flow must have in order to be revalidated when
	    revalidation duration exceeds half of max-revalidator  config  vari-
	    able.

	    The default is 5.

     other_config : offloaded-stats-delay: optional string, containing an inte-
     ger, at least 0
	    Set  worst case delay (in ms) it might take before statistics of of-
	    floaded flows are updated. Offloaded flows younger than  this  delay
	    will  always  be  revalidated regardless of other_config:min-revali-
	    date-pps.

	    The default is 2000.

     other_config : hw-offload: optional string, either true or false
	    Set this value to true to enable netdev flow offload.

	    The default value is false. Changing this value requires  restarting
	    the daemon

	    Currently  Open  vSwitch  supports hardware offloading on Linux sys-
	    tems. On other systems, this value is ignored. This functionality is
	    considered 'experimental'. Depending on which OpenFlow  matches  and
	    actions are configured, which kernel version is used, and what hard-
	    ware is available, Open vSwitch may not be able to offload function-
	    ality to hardware.

	    In order to dump HW offloaded flows use ovs-appctl dpctl/dump-flows,
	    ovs-dpctl  doesn't	support  this functionality. See ovs-vswitchd(8)
	    for details.

     other_config : n-offload-threads: optional string, containing an integer,
     in range 1 to 10
	    Set this value to the number of threads created to	manage	hardware
	    offloads.

	    The  default value is 1. Changing this value requires restarting the
	    daemon.

	    This is only relevant for userspace datapath and only if  other_con-
	    fig:hw-offload is enabled.

     other_config : tc-policy: optional string, one of none, skip_hw, or skip_sw
	    Specified the policy used with HW offloading. Options:

	    none   Add software rule and offload rule to HW.

	    skip_sw
		   Offload rule to HW only.

	    skip_hw
		   Add software rule without offloading rule to HW.

	    This is only relevant if other_config:hw-offload is enabled.

	    The default value is none.

     other_config : dpdk-init: optional string, one of false, true, or try
	    Set  this  value  to  true or try to enable runtime support for DPDK
	    ports. The vswitch must have compile-time support for DPDK as well.

	    A value of true will cause the ovs-vswitchd process to abort if DPDK
	    cannot be initialized. A value of try will	allow  the  ovs-vswitchd
	    process to continue running even if DPDK cannot be initialized.

	    The  default value is false. Changing this value requires restarting
	    the daemon

	    If this value is false at startup, any dpdk ports which are  config-
	    ured in the bridge will fail due to memory errors.

     other_config : dpdk-lcore-mask: optional string, containing an integer, at
     least 1
	    Specifies  the CPU cores where dpdk lcore threads should be spawned.
	    The DPDK lcore threads are used for DPDK library tasks, such as  li-
	    brary  internal message processing, logging, etc. Value should be in
	    the form of a hex string (so '0x123') similar to the 'taskset'  mask
	    input.

	    The  lowest  order	bit corresponds to the first CPU core. A set bit
	    means the corresponding core is available and an lcore  thread  will
	    be	created and pinned to it. If the input does not cover all cores,
	    those uncovered cores are considered not set.

	    For performance reasons, it is best to set this to a single core  on
	    the system, rather than allow lcore threads to float.

	    If	not specified, the value will be determined by choosing the low-
	    est CPU core from initial cpu affinity list.  Otherwise,  the  value
	    will be passed directly to the DPDK library.

     other_config : pmd-cpu-mask: optional string
	    Specifies  CPU  mask  for setting the cpu affinity of PMD (Poll Mode
	    Driver) threads. Value should be in the form of hex string,  similar
	    to the dpdk EAL '-c COREMASK' option input or the 'taskset' mask in-
	    put.

	    The  lowest  order	bit corresponds to the first CPU core. A set bit
	    means the corresponding core is available and a pmd thread	will  be
	    created  and  pinned  to  it. If the input does not cover all cores,
	    those uncovered cores are considered not set.

	    If not specified, one pmd thread will be created for each numa  node
	    and pinned to any available core on the numa node by default.

     other_config : dpdk-alloc-mem: optional string, containing an integer, at
     least 0
	    Specifies  the  amount  of	memory	to preallocate from the hugepage
	    pool, regardless of socket. It is recommended  that  dpdk-socket-mem
	    is used instead.

     other_config : dpdk-socket-mem: optional string
	    Specifies  the  amount  of	memory	to preallocate from the hugepage
	    pool, on a per-socket basis.

	    The specifier is a comma-separated string, in ascending order of CPU
	    socket. E.g. On a four socket system 1024,0,2048 would set socket  0
	    to preallocate 1024MB, socket 1 to preallocate 0MB, socket 2 to pre-
	    allocate 2048MB and socket 3 (no value given) to preallocate 0MB.

	    If	other_config:dpdk-socket-mem and other_config:dpdk-alloc-mem are
	    not specified, neither will be used and there  will  be  no  default
	    value  for	each  numa  node. DPDK defaults will be used instead. If
	    other_config:dpdk-socket-mem  and  other_config:dpdk-alloc-mem   are
	    specified  at  the	same  time, other_config:dpdk-socket-mem will be
	    used as default. Changing this value requires restarting the daemon.

     other_config : dpdk-socket-limit: optional string
	    Limits the maximum amount of  memory  that	can  be  used  from  the
	    hugepage pool, on a per-socket basis.

	    The specifier is a comma-separated list of memory limits per socket.
	    0 will disable the limit for a particular socket.

	    If not specified, OVS will not configure limits by default. Changing
	    this value requires restarting the daemon.

     other_config : dpdk-hugepage-dir: optional string
	    Specifies the path to the hugetlbfs mount point.

	    If	not specified, this will be guessed by the DPDK library (default
	    is /dev/hugepages). Changing this value requires restarting the dae-
	    mon.

     other_config : dpdk-extra: optional string
	    Specifies additional eal command line arguments for DPDK.

	    The default is empty. Changing this value  requires  restarting  the
	    daemon

     other_config : vhost-sock-dir: optional string
	    Specifies a relative path from external_ids:rundir to the vhost-user
	    unix  domain  socket  files. If this value is unset, the sockets are
	    put directly in external_ids:rundir.

	    Changing this value requires restarting the daemon.

     other_config : vhost-iommu-support: optional string, either true or false
	    vHost IOMMU is a security feature, which restricts the vhost  memory
	    that  a virtio device may access. vHost IOMMU support is disabled by
	    default, due to a bug in QEMU implementations of the vhost REPLY_ACK
	    protocol, (on which vHost IOMMU relies)  prior  to	v2.9.1.  Setting
	    this value to true enables vHost IOMMU support for vHost User Client
	    ports in OvS-DPDK, starting from DPDK v17.11.

	    Changing this value requires restarting the daemon.

     other_config : vhost-postcopy-support: optional string, either true or
     false
	    vHost  post-copy  is a feature which allows switching live migration
	    of VM attached to dpdkvhostuserclient port to post-copy mode if  de-
	    fault  pre-copy  migration can not be converged or takes too long to
	    converge. Setting this value to true enables vHost post-copy support
	    for all dpdkvhostuserclient  ports.  Available  starting  from  DPDK
	    v18.11 and QEMU 2.12.

	    Changing this value requires restarting the daemon.

     other_config : per-port-memory: optional string, either true or false
	    By	default OVS DPDK uses a shared memory model wherein devices that
	    have the same MTU and socket values can share the same mempool. Set-
	    ting this value to true changes this behaviour. Per port memory  al-
	    low  DPDK devices to use private memory per device. This can provide
	    greater transparency as regards memory usage but potentially at  the
	    cost of greater memory requirements.

	    Changing  this value requires restarting the daemon if dpdk-init has
	    already been set to true.

     other_config : tx-flush-interval: optional string, containing an integer,
     in range 0 to 1,000,000
	    Specifies the time in microseconds that a packet can wait in  output
	    batch  for	sending  i.e. amount of time that packet can spend in an
	    intermediate output queue before sending to netdev. This option  can
	    be	used  to configure balance between throughput and latency. Lower
	    values decreases latency  while  higher  values  may  be  useful  to
	    achieve higher performance.

	    Defaults to 0 i.e. instant packet sending (latency optimized).

     other_config : pmd-perf-metrics: optional string, either true or false
	    Enables  recording	of detailed PMD performance metrics for analysis
	    and trouble-shooting. This can have a performance impact in the  or-
	    der of 1%.

	    Defaults to false but can be changed at any time.

     other_config : smc-enable: optional string, either true or false
	    Signature  match  cache  or  SMC is a cache between EMC and megaflow
	    cache. It does not store the full key of the flow,	so  it	is  more
	    memory  efficient  comparing  to EMC cache. SMC is especially useful
	    when flow count is larger than EMC capacity.

	    Defaults to false but can be changed at any time.

     other_config : pmd-rxq-assign: optional string, one of cycles, group, or
     roundrobin
	    Specifies how RX queues will be automatically assigned to CPU cores.
	    Options:

	    cycles
		   Rxqs will be sorted by order of  measured  processing  cycles
		   before being assigned to CPU cores.

	    roundrobin
		   Rxqs will be round-robined across CPU cores.

	    group  Rxqs  will  be  sorted by order of measured processing cycles
		   before being assigned to  CPU  cores  with  lowest  estimated
		   load.

	    The default value is cycles.

	    Changing  this  value will affect an automatic re-assignment of Rxqs
	    to CPUs. Note: Rxqs mapped to CPU cores  with  pmd-rxq-affinity  are
	    unaffected.

     other_config : pmd-rxq-isolate: optional string, either true or false
	    Specifies  if a CPU core will be isolated after being pinned with an
	    Rx queue.

	    Set this value to false to non-isolate a CPU core after it is pinned
	    with an Rxq using pmd-rxq-affinity. This will allow  OVS  to  assign
	    other Rxqs to that CPU core.

	    The default value is true.

	    This can only be false when pmd-rxq-assign is set to group.

     other_config : n-handler-threads: optional string, containing an integer,
     at least 1
	    Attempts  to specify the number of threads for software datapaths to
	    use for handling new flows. Some datapaths may choose to ignore this
	    and it will be set to a sensible option for the datapath type.

	    This configuration is per datapath. If you have more than one  soft-
	    ware  datapath  (e.g.  some system bridges and some netdev bridges),
	    then the total number of threads is n-handler-threads times the num-
	    ber of software datapaths.

     other_config : n-revalidator-threads: optional string, containing an inte-
     ger, at least 1
	    Attempts to specify the number of threads for software datapaths  to
	    use  for  revalidating  flows  in  the  datapath. Some datapaths may
	    choose to ignore this and will set to  a  sensible	option	for  the
	    datapath type.

	    Typically,	there  is  a  direct  correlation  between the number of
	    revalidator threads, and the number of flows allowed  in  the  data-
	    path.  The	default  is the number of cpu cores divided by four plus
	    one. If n-handler-threads is set, the default changes to the  number
	    of cpu cores minus the number of handler threads.

	    This  configuration is per datapath. If you have more than one soft-
	    ware datapath (e.g. some system bridges and  some  netdev  bridges),
	    then the total number of threads is n-handler-threads times the num-
	    ber of software datapaths.

     other_config : emc-insert-inv-prob: optional string, containing an integer,
     in range 0 to 4,294,967,295
	    Specifies  the inverse probability (1/emc-insert-inv-prob) of a flow
	    being inserted into the Exact Match Cache (EMC). On average  one  in
	    every  emc-insert-inv-prob	packets that generate a unique flow will
	    cause an insertion into the EMC. A value of 1 will result in an  in-
	    sertion for every flow (1/1 = 100%) whereas a value of zero will re-
	    sult in no insertions and essentially disable the EMC.

	    Defaults to 100 ie. there is (1/100 =) 1% chance of EMC insertion.

     other_config : vlan-limit: optional string, containing an integer, at least
     0
	    Limits  the number of VLAN headers that can be matched to the speci-
	    fied number. Further VLAN headers will be treated as payload, e.g. a
	    packet with more 802.1q headers will match Ethernet type 0x8100.

	    Open vSwitch userspace currently supports at most 2 VLANs, and  each
	    datapath  has  its own limit. If vlan-limit is nonzero, it acts as a
	    further limit.

	    If this value is absent, the default is currently 1. This  maintains
	    backward  compatibility  with controllers that were designed for use
	    with Open vSwitch versions earlier than 2.8,  which  only  supported
	    one VLAN.

     other_config : bundle-idle-timeout: optional string, containing an integer,
     at least 1
	    The  maximum time (in seconds) that idle bundles will wait to be ex-
	    pired since it was either opened, modified or closed.

	    OpenFlow specification mandates the timeout to be at least one  sec-
	    ond. The default is 10 seconds.

     other_config : offload-rebalance: optional string, either true or false
	    Configures	HW  offload  rebalancing, that allows to dynamically of-
	    fload and un-offload flows while an offload-device	is  out  of  re-
	    sources  (OOR). This policy allows flows to be selected for offload-
	    ing based on the packets-per-second (pps) rate of flows.

	    Set this value to true to enable this option.

	    The default value is false. Changing this value requires  restarting
	    the daemon.

	    This is only relevant if HW offloading is enabled (hw-offload). When
	    this  policy  is  enabled, it also requires 'tc-policy' to be set to
	    'skip_sw'.

     other_config : pmd-auto-lb: optional string, either true or false
	    Configures PMD Auto Load Balancing that allows automatic  assignment
	    of RX queues to PMDs if any of PMDs is overloaded (i.e. a processing
	    cycles > other_config:pmd-auto-lb-load-threshold).

	    It	uses  current scheme of cycle based assignment of RX queues that
	    are not statically pinned to PMDs.

	    The default value is false.

	    Set this value to true to enable this option. It is  currently  dis-
	    abled by default and an experimental feature.

	    This  only	comes in effect if cycle based assignment is enabled and
	    there are more than one non-isolated PMDs present and at  least  one
	    of it polls more than one queue.

     other_config : pmd-auto-lb-rebal-interval: optional string, containing an
     integer, in range 0 to 20,000
	    The  minimum time (in minutes) 2 consecutive PMD Auto Load Balancing
	    iterations.

	    The defaul value is 1 min. If configured to 0 then it would be  con-
	    verted to default value i.e. 1 min

	    This option can be configured to avoid frequent trigger of auto load
	    balancing  of PMDs. For e.g. set the value (in min) such that it oc-
	    curs once in few hours or a day or a week.

     other_config : pmd-auto-lb-load-threshold: optional string, containing an
     integer, in range 0 to 100
	    Specifies the minimum PMD thread load threshold (% of  used  cycles)
	    of	any non-isolated PMD threads when a PMD Auto Load Balance may be
	    triggered.

	    The default value is 95%.

     other_config : pmd-auto-lb-improvement-threshold: optional string, contain-
     ing an integer, in range 0 to 100
	    Specifies the minimum evaluated % improvement in  load  distribution
	    across  the non-isolated PMD threads that will allow a PMD Auto Load
	    Balance to occur.

	    Note, setting this parameter to 0 will always  allow  an  auto  load
	    balance to occur regardless of estimated improvement or not.

	    The default value is 25%.

     other_config : userspace-tso-enable: optional string, either true or false
	    Set this value to true to enable userspace support for TCP Segmenta-
	    tion  Offloading  (TSO). When it is enabled, the interfaces can pro-
	    vide an oversized TCP segment to the datapath and the datapath  will
	    offload  the TCP segmentation and checksum calculation to the inter-
	    faces when necessary.

	    The default value is false. Changing this value requires  restarting
	    the daemon.

	    The feature only works if Open vSwitch is built with DPDK support.

	    The feature is considered experimental.

   Status:

     next_cfg: integer
	    Sequence  number for client to increment. When a client modifies any
	    part of the database configuration	and  wishes  to  wait  for  Open
	    vSwitch  to  finish  applying the changes, it may increment this se-
	    quence number.

     cur_cfg: integer
	    Sequence number that Open vSwitch  sets  to  the  current  value  of
	    next_cfg after it finishes applying a set of configuration changes.

     dpdk_initialized: boolean
	    True  if  other_config:dpdk-init is set to true and the DPDK library
	    is successfully initialized.

   Statistics:

     The statistics column contains key-value pairs that report statistics about
     a system running an Open vSwitch.	These  are  updated  periodically  (cur-
     rently, every 5 seconds). Key-value pairs that cannot be determined or that
     do not apply to a platform are omitted.

     other_config : enable-statistics: optional string, either true or false
	    Statistics	are  disabled by default to avoid overhead in the common
	    case when statistics gathering is not useful. Set this value to true
	    to enable populating the statistics column or to false to explicitly
	    disable it.

     statistics : cpu: optional string, containing an integer, at least 1
	    Number of CPU processors, threads, or  cores  currently  online  and
	    available  to the operating system on which Open vSwitch is running,
	    as an integer. This may be less than the number installed,	if  some
	    are not online or if they are not available to the operating system.

	    Open  vSwitch  userspace  processes  are  not multithreaded, but the
	    Linux kernel-based datapath is.

     statistics : load_average: optional string
	    A comma-separated list of three floating-point numbers, representing
	    the system load average over the last 1, 5, and 15 minutes,  respec-
	    tively.

     statistics : memory: optional string
	    A comma-separated list of integers, each of which represents a quan-
	    tity  of  memory in kilobytes that describes the operating system on
	    which Open vSwitch is running. In  respective  order,  these  values
	    are:

	    1.	Total amount of RAM allocated to the OS.

	    2.	RAM allocated to the OS that is in use.

	    3.	RAM  that  can	be flushed out to disk or otherwise discarded if
		that space is needed for another purpose. This number is  neces-
		sarily less than or equal to the previous value.

	    4.	Total disk space allocated for swap.

	    5.	Swap space currently in use.

	    On	Linux,	all  five  values can be determined and are included. On
	    other operating systems, only the first two  values  can  be  deter-
	    mined, so the list will only have two values.

     statistics : process_NAME: optional string
	    One  such key-value pair, with NAME replaced by a process name, will
	    exist for each running Open vSwitch daemon process,  with  name  re-
	    placed  by	the daemon's name (e.g. process_ovs-vswitchd). The value
	    is a comma-separated list of integers. The	integers  represent  the
	    following,	with  memory measured in kilobytes and durations in mil-
	    liseconds:

	    1.	The process's virtual memory size.

	    2.	The process's resident set size.

	    3.	The amount of user and system CPU time consumed by the process.

	    4.	The number of times that the process has crashed and been  auto-
		matically restarted by the monitor.

	    5.	The duration since the process was started.

	    6.	The duration for which the process has been running.

	    The  interpretation  of  some of these values depends on whether the
	    process was started with the --monitor. If	it  was  not,  then  the
	    crash  count  will	always be 0 and the two durations will always be
	    the same. If --monitor was given, then the crash count may be  posi-
	    tive;  if it is, the latter duration is the amount of time since the
	    most recent crash and restart.

	    There will be one key-value pair for each  file  in  Open  vSwitch's
	    ``run  directory'' (usually /var/run/openvswitch) whose name ends in
	    .pid, whose contents are a process ID, and which is locked by a run-
	    ning process. The name is taken from the pidfile's name.

	    Currently Open vSwitch is only able to obtain all of the  above  de-
	    tail  on  Linux  systems. On other systems, the same key-value pairs
	    will be present but the values will always be the empty string.

     statistics : file_systems: optional string
	    A space-separated list of information on local, writable  file  sys-
	    tems.  Each  item in the list describes one file system and consists
	    in turn of a comma-separated list of the following:

	    1.	Mount point, e.g. / or /var/log. Any spaces  or  commas  in  the
		mount point are replaced by underscores.

	    2.	Total size, in kilobytes, as an integer.

	    3.	Amount of storage in use, in kilobytes, as an integer.

	    This  key-value pair is omitted if there are no local, writable file
	    systems or if Open vSwitch cannot obtain the needed information.

   Version Reporting:

     These columns report the types and versions of the  hardware  and	software
     running  Open  vSwitch.  We  recommend in general that software should test
     whether specific features are supported instead of relying on version  num-
     ber  checks. These values are primarily intended for reporting to human ad-
     ministrators.

     ovs_version: optional string
	    The Open vSwitch version number, e.g. 1.1.0.

     db_version: optional string
	    The database schema version number, e.g.  1.2.3.  See  ovsdb-tool(1)
	    for an explanation of the numbering scheme.

	    The schema version is part of the database schema, so it can also be
	    retrieved  by  fetching  the  schema using the Open vSwitch database
	    protocol.

     system_type: optional string
	    An identifier for the type of system on top of  which  Open  vSwitch
	    runs, e.g. XenServer or KVM.

	    System  integrators  are responsible for choosing and setting an ap-
	    propriate value for this column.

     system_version: optional string
	    The  version  of  the  system  identified	by   system_type,   e.g.
	    5.6.100-39265p on XenServer 5.6.100 build 39265.

	    System  integrators  are responsible for choosing and setting an ap-
	    propriate value for this column.

     dpdk_version: optional string
	    The version of the linked DPDK library.

   Capabilities:

     These columns report capabilities of the Open vSwitch instance.

     datapath_types: set of strings
	    This column reports the different dpifs registered with the  system.
	    These  are	the  values  that  this  instance  supports in the data-
	    path_type column of the Bridge table.

     iface_types: set of strings
	    This column reports the different netdevs registered with  the  sys-
	    tem.  These  are  the values that this instance supports in the type
	    column of the Interface table.

   Database Configuration:

     These columns primarily configure the Open vSwitch database (ovsdb-server),
     not the Open vSwitch switch (ovs-vswitchd). The OVSDB  database  also  uses
     the ssl settings.

     The  Open	vSwitch switch does read the database configuration to determine
     remote IP addresses to which in-band control should apply.

     manager_options: set of Managers
	    Database clients to which the Open vSwitch	database  server  should
	    connect  or  to  which  it should listen, along with options for how
	    these connections should be configured. See the  Manager  table  for
	    more information.

	    For  this  column to serve its purpose, ovsdb-server must be config-
	    ured to  honor  it.  The  easiest  way  to	do  this  is  to  invoke
	    ovsdb-server	  with		the	    option	   --re-
	    mote=db:Open_vSwitch,Open_vSwitch,manager_options	 The	 startup
	    scripts that accompany Open vSwitch do this by default.

   IPsec:

     These  settings  control the global configuration of IPsec tunnels. The op-
     tions column of the Interface table configures IPsec  for	individual  tun-
     nels.

     OVS  IPsec supports the following three forms of authentication. Currently,
     all IPsec tunnels must use the same form:

	    1.	Pre-shared keys: Omit the global settings. On each  tunnel,  set
		options:psk.

	    2.	Self-signed  certificates:  Set  the private_key and certificate
		global settings. On each tunnel,  set  options:remote_cert.  The
		remote certificate can be self-signed.

	    3.	CA-signed  certificates: Set all of the global settings. On each
		tunnel, set options:remote_name to the common name (CN)  of  the
		remote certificate. The remote certificate must be signed by the
		CA.

     other_config : private_key: optional string
	    Name  of  a PEM file containing the private key used as the switch's
	    identity for IPsec tunnels.

     other_config : certificate: optional string
	    Name of a PEM file	containing  a  certificate  that  certifies  the
	    switch's  private key, and identifies a trustworthy switch for IPsec
	    tunnels. The certificate must be x.509 version 3 and with the string
	    in common name (CN) also set in the subject alternative name (SAN).

     other_config : ca_cert: optional string
	    Name of a PEM file containing the CA certificate used to verify that
	    a remote switch of the IPsec tunnel is trustworthy.

   Plaintext Tunnel Policy:

     When an IPsec tunnel is configured in this database,  multiple  independent
     components  take  responsibility  for implementing it. ovs-vswitchd and its
     datapath handle packet forwarding to  the	tunnel	and  a	separate  daemon
     pushes  the  tunnel's IPsec policy configuration to the kernel or other en-
     tity that implements it. There is a race: if the former configuration  com-
     pletes before the latter, then packets sent by the local host over the tun-
     nel  can  be  transmitted	in  plaintext. Using this setting, OVS users can
     avoid this undesirable situation.

     other_config : ipsec_skb_mark: optional string
	    This setting takes the form value/mask. If it is specified, then the
	    skb_mark field in every outgoing tunneled packet sent  in  plaintext
	    is	compared  against  it and, if it matches, the packet is dropped.
	    This is a global setting that is applied to every  tunneled  packet,
	    regardless	of  whether  IPsec encryption is enabled for the tunnel,
	    the type of tunnel, or whether OVS is involved.

	    Example policies:

	    1/1    Drop all unencrypted tunneled packets in which the least-sig-
		   nificant bit of skb_mark is 1. This would be a useful  policy
		   given  an  OpenFlow	flow  table  that sets skb_mark to 1 for
		   traffic that should be encrypted. The default skb_mark is  0,
		   so this would not affect other traffic.

	    0/1    Drop all unencrypted tunneled packets in which the least-sig-
		   nificant  bit of skb_mark is 0. This would be a useful policy
		   if no unencrypted tunneled traffic  should  exit  the  system
		   without being specially permitted by setting skb_mark to 1.

	    (empty)
		   If  this setting is empty or unset, then all unencrypted tun-
		   neled packets are transmitted in the usual way.

   Common Columns:

     The overall purpose of these columns is described under Common  Columns  at
     the beginning of this document.

     other_config: map of string-string pairs

     external_ids: map of string-string pairs

Bridge TABLE
     Configuration for a bridge within an Open_vSwitch.

     A	Bridge	record represents an Ethernet switch with one or more ``ports,''
     which are the Port records pointed to by the Bridge's ports column.

   Summary:
     Core Features:
       name			   immutable string (must be unique  within  ta-
				   ble)
       ports			   set of Ports
       mirrors			   set of Mirrors
       netflow			   optional NetFlow
       sflow			   optional sFlow
       ipfix			   optional IPFIX
       flood_vlans		   set	of  up	to 4,096 integers, in range 0 to
				   4,095
       auto_attach		   optional AutoAttach
     OpenFlow Configuration:
       controller		   set of Controllers
       flow_tables		   map of integer-Flow_Table pairs, key in range
				   0 to 254
       fail_mode		   optional string, either secure or standalone
       datapath_id		   optional string
       datapath_version 	   string
       other_config : datapath-id
				   optional string
       other_config : dp-desc	   optional string
       other_config : dp-sn	   optional string
       other_config : disable-in-band
				   optional string, either true or false
       other_config : in-band-queue
				   optional string, containing	an  integer,  in
				   range 0 to 4,294,967,295
       other_config : controller-queue-size
				   optional  string,  containing  an integer, in
				   range 1 to 512
       protocols		   set of  strings,  one  of  OpenFlow10,  Open-
				   Flow11,  OpenFlow12,  OpenFlow13, OpenFlow14,
				   or OpenFlow15
     Spanning Tree Configuration:
       STP Configuration:
	  stp_enable		   boolean
	  other_config : stp-system-id
				   optional string
	  other_config : stp-priority
				   optional string, containing	an  integer,  in
				   range 0 to 65,535
	  other_config : stp-hello-time
				   optional  string,  containing  an integer, in
				   range 1 to 10
	  other_config : stp-max-age
				   optional string, containing	an  integer,  in
				   range 6 to 40
	  other_config : stp-forward-delay
				   optional  string,  containing  an integer, in
				   range 4 to 30
	  other_config : mcast-snooping-aging-time
				   optional string, containing	an  integer,  at
				   least 1
	  other_config : mcast-snooping-table-size
				   optional  string,  containing  an integer, at
				   least 1
	  other_config : mcast-snooping-disable-flood-unregistered
				   optional string, either true or false
       STP Status:
	  status : stp_bridge_id   optional string
	  status : stp_designated_root
				   optional string
	  status : stp_root_path_cost
				   optional string
     Rapid Spanning Tree:
       RSTP Configuration:
	  rstp_enable		   boolean
	  other_config : rstp-address
				   optional string
	  other_config : rstp-priority
				   optional string, containing	an  integer,  in
				   range 0 to 61,440
	  other_config : rstp-ageing-time
				   optional  string,  containing  an integer, in
				   range 10 to 1,000,000
	  other_config : rstp-force-protocol-version
				   optional string, containing an integer
	  other_config : rstp-max-age
				   optional string, containing	an  integer,  in
				   range 6 to 40
	  other_config : rstp-forward-delay
				   optional  string,  containing  an integer, in
				   range 4 to 30
	  other_config : rstp-transmit-hold-count
				   optional string, containing	an  integer,  in
				   range 1 to 10
       RSTP Status:
	  rstp_status : rstp_bridge_id
				   optional string
	  rstp_status : rstp_root_id
				   optional string
	  rstp_status : rstp_root_path_cost
				   optional  string,  containing  an integer, at
				   least 0
	  rstp_status : rstp_designated_id
				   optional string
	  rstp_status : rstp_designated_port_id
				   optional string
	  rstp_status : rstp_bridge_port_id
				   optional string
     Multicast Snooping Configuration:
       mcast_snooping_enable	   boolean
     Other Features:
       datapath_type		   string
       external_ids : bridge-id    optional string
       external_ids : xs-network-uuids
				   optional string
       other_config : hwaddr	   optional string
       other_config : forward-bpdu
				   optional string, either true or false
       other_config : mac-aging-time
				   optional string, containing	an  integer,  at
				   least 1
       other_config : mac-table-size
				   optional  string,  containing  an integer, at
				   least 1
     Common Columns:
       other_config		   map of string-string pairs
       external_ids		   map of string-string pairs

   Details:
   Core Features:

     name: immutable string (must be unique within table)
	    Bridge identifier. Must be unique among the names of  ports,  inter-
	    faces, and bridges on a host.

	    The  name must be alphanumeric and must not contain forward or back-
	    ward slashes. The name of a bridge is also the name of an  Interface
	    (and a Port) within the bridge, so the restrictions on the name col-
	    umn  in  the  Interface table, particularly on length, also apply to
	    bridge names. Refer to the documentation for Interface names for de-
	    tails.

     ports: set of Ports
	    Ports included in the bridge.

     mirrors: set of Mirrors
	    Port mirroring configuration.

     netflow: optional NetFlow
	    NetFlow configuration.

     sflow: optional sFlow
	    sFlow(R) configuration.

     ipfix: optional IPFIX
	    IPFIX configuration.

     flood_vlans: set of up to 4,096 integers, in range 0 to 4,095
	    VLAN IDs of VLANs on which MAC address learning should be  disabled,
	    so	that packets are flooded instead of being sent to specific ports
	    that are believed to contain packets' destination MACs. This  should
	    ordinarily be used to disable MAC learning on VLANs used for mirror-
	    ing (RSPAN VLANs). It may also be useful for debugging.

	    SLB  bonding  (see the bond_mode column in the Port table) is incom-
	    patible with flood_vlans. Consider using another bonding mode  or  a
	    different type of mirror instead.

     auto_attach: optional AutoAttach
	    Auto Attach configuration.

   OpenFlow Configuration:

     controller: set of Controllers
	    OpenFlow controller set. If unset, then no OpenFlow controllers will
	    be used.

	    If	there  are  primary controllers, removing all of them clears the
	    OpenFlow flow tables, group table, and meter table. If there are  no
	    primary  controllers,  adding  one	also  clears these tables. Other
	    changes to the set of controllers, such as adding or removing a ser-
	    vice controller, adding another primary controller to supplement  an
	    existing  primary  controller,  or	removing only one of two primary
	    controllers, have no effect on these tables.

     flow_tables: map of integer-Flow_Table pairs, key in range 0 to 254
	    Configuration for OpenFlow tables. Each pair maps from  an	OpenFlow
	    table ID to configuration for that table.

     fail_mode: optional string, either secure or standalone
	    When  a controller is configured, it is, ordinarily, responsible for
	    setting up all flows on the switch. Thus, if the connection  to  the
	    controller	fails,	no new network connections can be set up. If the
	    connection to the controller stays down long enough, no packets  can
	    pass through the switch at all. This setting determines the switch's
	    response to such a situation. It may be set to one of the following:

	    standalone
		   If no message is received from the controller for three times
		   the	inactivity  probe  interval (see inactivity_probe), then
		   Open vSwitch will take over	responsibility	for  setting  up
		   flows.  In  this  mode, Open vSwitch causes the bridge to act
		   like an ordinary MAC-learning switch. Open vSwitch will  con-
		   tinue to retry connecting to the controller in the background
		   and,  when  the  connection succeeds, it will discontinue its
		   standalone behavior.

	    secure
		   Open vSwitch will not set up flows on its own when  the  con-
		   troller  connection fails or when no controllers are defined.
		   The bridge will continue to retry connecting to  any  defined
		   controllers forever.

	    The default is standalone if the value is unset, but future versions
	    of Open vSwitch may change the default.

	    The standalone mode can create forwarding loops on a bridge that has
	    more  than	one uplink port unless STP is enabled. To avoid loops on
	    such a bridge, configure secure mode or enable STP (see stp_enable).

	    The fail_mode setting applies only to primary controllers. When more
	    than one primary controller is configured, fail_mode  is  considered
	    only when none of the configured controllers can be contacted.

	    Changing fail_mode when no primary controllers are configured clears
	    the OpenFlow flow tables, group table, and meter table.

     datapath_id: optional string
	    Reports  the  OpenFlow  datapath  ID  in use. Exactly 16 hex digits.
	    (Setting this column has no useful	effect.  Set  other-config:data-
	    path-id instead.)

     datapath_version: string
	    Reports  the  datapath  version. This column is maintained for back-
	    wards compatibility. The preferred	locatation  is	the  datapath_id
	    column of the Datapath table. The full documentation for this column
	    is there.

     other_config : datapath-id: optional string
	    Overrides the default OpenFlow datapath ID, setting it to the speci-
	    fied  value specified in hex. The value must either have a 0x prefix
	    or be exactly 16 hex digits long. May not be all-zero.

     other_config : dp-desc: optional string
	    Human readable description of datapath. It is a  maximum  256  byte-
	    long  free-form  string  to describe the datapath for debugging pur-
	    poses, e.g. switch3 in room 3120.  The  value  is  returned  by  the
	    switch  as	a  part  of  reply to OFPMP_DESC request (ofp_desc). The
	    OpenFlow specification (e.g. 1.3.5) describes the ofp_desc structure
	    to contaion "NULL terminated ASCII strings". For  the  compatibility
	    reasons no more than 255 ASCII characters should be used.

     other_config : dp-sn: optional string
	    Serial number. It is a maximum 32 byte-long free-form string to pro-
	    vide  an  additional switch identification. The value is returned by
	    the switch as a part of reply to OFPMP_DESC request (ofp_desc). Same
	    as mentioned in the description of other-config:dp-desc, the  string
	    should be no more than 31 ASCII characters for the compatibility.

     other_config : disable-in-band: optional string, either true or false
	    If	set to true, disable in-band control on the bridge regardless of
	    controller and manager settings.

     other_config : in-band-queue: optional string, containing an integer, in
     range 0 to 4,294,967,295
	    A queue ID as a nonnegative integer. This sets the OpenFlow queue ID
	    that will be used by flows set up by in-band control on this bridge.
	    If unset, or if the port used by an in-band control  flow  does  not
	    have  QoS  configured, or if the port does not have a queue with the
	    specified ID, the default queue is used instead.

     other_config : controller-queue-size: optional string, containing an inte-
     ger, in range 1 to 512
	    This sets the maximum size of the queue of packets that need  to  be
	    sent  to  the OpenFlow management controller. The value must be less
	    than 512. If not specified the queue size is limited to 100  packets
	    by	default.  Note:  increasing the queue size might have a negative
	    impact on latency.

     protocols: set of strings, one of OpenFlow10, OpenFlow11, OpenFlow12, Open-
     Flow13, OpenFlow14, or OpenFlow15
	    List of OpenFlow protocols that may be used when negotiating a  con-
	    nection with a controller. OpenFlow 1.0, 1.1, 1.2, 1.3, 1.4, and 1.5
	    are enabled by default if this column is empty.

   Spanning Tree Configuration:

     The IEEE 802.1D Spanning Tree Protocol (STP) is a network protocol that en-
     sures loop-free topologies. It allows redundant links to be included in the
     network to provide automatic backup paths if the active links fails.

     These  settings configure the slower-to-converge but still widely supported
     version of Spanning Tree Protocol, sometimes  known  as  802.1D-1998.  Open
     vSwitch  also supports the newer Rapid Spanning Tree Protocol (RSTP), docu-
     mented later in the section titled Rapid Spanning Tree Configuration.

   STP Configuration:

     stp_enable: boolean
	    Enable spanning tree on the bridge. By default, STP is  disabled  on
	    bridges. Bond, internal, and mirror ports are not supported and will
	    not participate in the spanning tree.

	    STP  and RSTP are mutually exclusive. If both are enabled, RSTP will
	    be used.

     other_config : stp-system-id: optional string
	    The bridge's STP identifier (the lower 48 bits of the bridge-id)  in
	    the  form  xx:xx:xx:xx:xx:xx.  By default, the identifier is the MAC
	    address of the bridge.

     other_config : stp-priority: optional string, containing an integer, in
     range 0 to 65,535
	    The bridge's relative priority value for determining the root bridge
	    (the upper 16 bits of the  bridge-id).  A  bridge  with  the  lowest
	    bridge-id is elected the root. By default, the priority is 0x8000.

     other_config : stp-hello-time: optional string, containing an integer, in
     range 1 to 10
	    The  interval  between transmissions of hello messages by designated
	    ports, in seconds. By default the hello interval is 2 seconds.

     other_config : stp-max-age: optional string, containing an integer, in
     range 6 to 40
	    The maximum age of the information transmitted by the bridge when it
	    is the root bridge, in seconds. By default, the maximum  age  is  20
	    seconds.

     other_config : stp-forward-delay: optional string, containing an integer,
     in range 4 to 30
	    The delay to wait between transitioning root and designated ports to
	    forwarding,  in seconds. By default, the forwarding delay is 15 sec-
	    onds.

     other_config : mcast-snooping-aging-time: optional string, containing an
     integer, at least 1
	    The maximum number of seconds to retain a multicast  snooping  entry
	    for  which	no  packets have been seen. The default is currently 300
	    seconds (5 minutes). The value, if specified, is forced into a  rea-
	    sonable range, currently 15 to 3600 seconds.

     other_config : mcast-snooping-table-size: optional string, containing an
     integer, at least 1
	    The maximum number of multicast snooping addresses to learn. The de-
	    fault  is  currently 2048. The value, if specified, is forced into a
	    reasonable range, currently 10 to 1,000,000.

     other_config : mcast-snooping-disable-flood-unregistered: optional string,
     either true or false
	    If set to false, unregistered multicast packets are forwarded to all
	    ports. If set to true, unregistered multicast packets are  forwarded
	    to ports connected to multicast routers.

   STP Status:

     These  key-value  pairs  report the status of 802.1D-1998. They are present
     only if STP is enabled (via the stp_enable column).

     status : stp_bridge_id: optional string
	    The bridge ID used in spanning  tree  advertisements,  in  the  form
	    xxxx.yyyyyyyyyyyy  where the xs are the STP priority, the ys are the
	    STP system ID, and each x and y is a hex digit.

     status : stp_designated_root: optional string
	    The designated root for this spanning tree, in the same form as sta-
	    tus:stp_bridge_id. If this bridge is the root, this  will  have  the
	    same value as status:stp_bridge_id, otherwise it will differ.

     status : stp_root_path_cost: optional string
	    The  path  cost of reaching the designated bridge. A lower number is
	    better. The value is 0 if this bridge is the root, otherwise  it  is
	    higher.

   Rapid Spanning Tree:

     Rapid  Spanning  Tree Protocol (RSTP), like STP, is a network protocol that
     ensures loop-free topologies. RSTP superseded STP with the  publication  of
     802.1D-2004. Compared to STP, RSTP converges more quickly and recovers more
     quickly from failures.

   RSTP Configuration:

     rstp_enable: boolean
	    Enable  Rapid  Spanning Tree on the bridge. By default, RSTP is dis-
	    abled on bridges. Bond, internal, and mirror ports are not supported
	    and will not participate in the spanning tree.

	    STP and RSTP are mutually exclusive. If both are enabled, RSTP  will
	    be used.

     other_config : rstp-address: optional string
	    The  bridge's  RSTP  address (the lower 48 bits of the bridge-id) in
	    the form xx:xx:xx:xx:xx:xx. By default, the address is the	MAC  ad-
	    dress of the bridge.

     other_config : rstp-priority: optional string, containing an integer, in
     range 0 to 61,440
	    The bridge's relative priority value for determining the root bridge
	    (the  upper  16  bits  of  the  bridge-id). A bridge with the lowest
	    bridge-id is elected the root. By default, the  priority  is  0x8000
	    (32768).  This  value needs to be a multiple of 4096, otherwise it's
	    rounded to the nearest inferior one.

     other_config : rstp-ageing-time: optional string, containing an integer, in
     range 10 to 1,000,000
	    The Ageing Time parameter for the Bridge. The default value  is  300
	    seconds.

     other_config : rstp-force-protocol-version: optional string, containing an
     integer
	    The  Force	Protocol Version parameter for the Bridge. This can take
	    the value 0 (STP Compatibility mode) or 2 (the default, normal oper-
	    ation).

     other_config : rstp-max-age: optional string, containing an integer, in
     range 6 to 40
	    The maximum age of the information transmitted by the Bridge when it
	    is the Root Bridge. The default value is 20.

     other_config : rstp-forward-delay: optional string, containing an integer,
     in range 4 to 30
	    The delay used by STP Bridges  to  transition  Root  and  Designated
	    Ports to Forwarding. The default value is 15.

     other_config : rstp-transmit-hold-count: optional string, containing an in-
     teger, in range 1 to 10
	    The  Transmit  Hold Count used by the Port Transmit state machine to
	    limit transmission rate. The default value is 6.

   RSTP Status:

     These key-value pairs report the status of 802.1D-2004.  They  are  present
     only if RSTP is enabled (via the rstp_enable column).

     rstp_status : rstp_bridge_id: optional string
	    The  bridge  ID  used  in rapid spanning tree advertisements, in the
	    form x.yyy.zzzzzzzzzzzz where x is the RSTP priority, the ys  are  a
	    locally  assigned system ID extension, the zs are the STP system ID,
	    and each x, y, or z is a hex digit.

     rstp_status : rstp_root_id: optional string
	    The root of this spanning  tree,  in  the  same  form  as  rstp_sta-
	    tus:rstp_bridge_id.  If  this bridge is the root, this will have the
	    same value as rstp_status:rstp_bridge_id, otherwise it will differ.

     rstp_status : rstp_root_path_cost: optional string, containing an integer,
     at least 0
	    The path cost of reaching the root. A lower number	is  better.  The
	    value is 0 if this bridge is the root, otherwise it is higher.

     rstp_status : rstp_designated_id: optional string
	    The   RSTP	 designated   ID,   in	 the   same  form  as  rstp_sta-
	    tus:rstp_bridge_id.

     rstp_status : rstp_designated_port_id: optional string
	    The RSTP designated port ID, as a 4-digit hex number.

     rstp_status : rstp_bridge_port_id: optional string
	    The RSTP bridge port ID, as a 4-digit hex number.

   Multicast Snooping Configuration:

     Multicast snooping (RFC 4541) monitors the Internet Group Management Proto-
     col (IGMP) and Multicast Listener Discovery traffic between hosts and  mul-
     ticast  routers.  The switch uses what IGMP and MLD snooping learns to for-
     ward multicast traffic only to interfaces that are connected to  interested
     receivers.  Currently  it	supports IGMPv1, IGMPv2, IGMPv3, MLDv1 and MLDv2
     protocols.

     mcast_snooping_enable: boolean
	    Enable multicast snooping on the bridge. For  now,	the  default  is
	    disabled.

   Other Features:

     datapath_type: string
	    Name  of datapath provider. The kernel datapath has type system. The
	    userspace datapath has type netdev. A manager may refer to the data-
	    path_types column of the Open_vSwitch table for a list of the  types
	    accepted by this Open vSwitch instance.

     external_ids : bridge-id: optional string
	    A  unique  identifier  of  the bridge. On Citrix XenServer this will
	    commonly be the same as external_ids:xs-network-uuids.

     external_ids : xs-network-uuids: optional string
	    Semicolon-delimited set of universally unique identifier(s) for  the
	    network  with  which this bridge is associated on a Citrix XenServer
	    host. The network identifiers are RFC 4122 UUIDs  as  displayed  by,
	    e.g., xe network-list.

     other_config : hwaddr: optional string
	    An	Ethernet  address in the form xx:xx:xx:xx:xx:xx to set the hard-
	    ware address of the local port and influence the datapath ID.

     other_config : forward-bpdu: optional string, either true or false
	    Controls forwarding of BPDUs and other network control  frames  when
	    NORMAL action is invoked. When this option is false or unset, frames
	    with  reserved Ethernet addresses (see table below) will not be for-
	    warded. When this option is true, such frames will	not  be  treated
	    specially.

	    The above general rule has the following exceptions:

	    *	   If STP is enabled on the bridge (see the stp_enable column in
		   the	Bridge	table),  the  bridge  processes all received STP
		   packets and never passes them to OpenFlow or  forwards  them.
		   This is true even if STP is disabled on an individual port.

	    *	   If  LLDP  is  enabled on an interface (see the lldp column in
		   the Interface table), the interface processes  received  LLDP
		   packets and never passes them to OpenFlow or forwards them.

	    Set  this option to true if the Open vSwitch bridge connects differ-
	    ent Ethernet networks and is not configured to participate in STP.

	    This option affects packets with the following destination	MAC  ad-
	    dresses:

	    01:80:c2:00:00:00
		   IEEE 802.1D Spanning Tree Protocol (STP).

	    01:80:c2:00:00:01
		   IEEE Pause frame.

	    01:80:c2:00:00:0x
		   Other reserved protocols.

	    00:e0:2b:00:00:00
		   Extreme Discovery Protocol (EDP).

	    00:e0:2b:00:00:04 and 00:e0:2b:00:00:06
		   Ethernet Automatic Protection Switching (EAPS).

	    01:00:0c:cc:cc:cc
		   Cisco Discovery Protocol (CDP), VLAN Trunking Protocol (VTP),
		   Dynamic  Trunking  Protocol	(DTP), Port Aggregation Protocol
		   (PAgP), and others.

	    01:00:0c:cc:cc:cd
		   Cisco Shared Spanning Tree Protocol PVSTP+.

	    01:00:0c:cd:cd:cd
		   Cisco STP Uplink Fast.

	    01:00:0c:00:00:00
		   Cisco Inter Switch Link.

	    01:00:0c:cc:cc:cx
		   Cisco CFM.

     other_config : mac-aging-time: optional string, containing an integer, at
     least 1
	    The maximum number of seconds to retain a  MAC  learning  entry  for
	    which  no  packets have been seen. The default is currently 300 sec-
	    onds (5 minutes). The value, if specified, is forced into a  reason-
	    able range, currently 15 to 3600 seconds.

	    A  short MAC aging time allows a network to more quickly detect that
	    a host is no longer connected to a switch  port.  However,	it  also
	    makes  it  more  likely  that packets will be flooded unnecessarily,
	    when they are addressed to a connected host  that  rarely  transmits
	    packets.  To reduce the incidence of unnecessary flooding, use a MAC
	    aging time longer than the maximum interval at which a host will or-
	    dinarily transmit packets.

     other_config : mac-table-size: optional string, containing an integer, at
     least 1
	    The maximum number of MAC addresses to learn. The  default	is  cur-
	    rently  8192.  The	value, if specified, is forced into a reasonable
	    range, currently 10 to 1,000,000.

   Common Columns:

     The overall purpose of these columns is described under Common  Columns  at
     the beginning of this document.

     other_config: map of string-string pairs

     external_ids: map of string-string pairs

Port TABLE
     A port within a Bridge.

     Most  commonly, a port has exactly one ``interface,'' pointed to by its in-
     terfaces column. Such a port logically corresponds to a port on a	physical
     Ethernet  switch.	A port with more than one interface is a ``bonded port''
     (see Bonding Configuration).

     Some properties that one might think as belonging to a  port  are	actually
     part of the port's Interface members.

   Summary:
     name			   immutable  string  (must be unique within ta-
				   ble)
     interfaces 		   set of 1 or more Interfaces
     VLAN Configuration:
       vlan_mode		   optional string, one of access, dot1q-tunnel,
				   native-tagged, native-untagged, or trunk
       tag			   optional integer, in range 0 to 4,095
       trunks			   set of up to 4,096 integers, in  range  0  to
				   4,095
       cvlans			   set	of  up	to 4,096 integers, in range 0 to
				   4,095
       other_config : qinq-ethtype
				   optional string, either 802.1ad or 802.1q
       other_config : priority-tags
				   optional string, one of  always,  if-nonzero,
				   or never
     Bonding Configuration:
       bond_mode		   optional  string,  one of active-backup, bal-
				   ance-slb, or balance-tcp
       other_config : bond-hash-basis
				   optional string, containing an integer
       other_config : lb-output-action
				   optional string, either true or false
       other_config : bond-primary
				   optional string
       Link Failure Detection:
	  other_config : bond-detect-mode
				   optional string, either carrier or miimon
	  other_config : bond-miimon-interval
				   optional string, containing an integer
	  bond_updelay		   integer
	  bond_downdelay	   integer
       LACP Configuration:
	  lacp			   optional string, one of active, off, or  pas-
				   sive
	  other_config : lacp-system-id
				   optional string
	  other_config : lacp-system-priority
				   optional  string,  containing  an integer, in
				   range 1 to 65,535
	  other_config : lacp-time
				   optional string, either fast or slow
	  other_config : lacp-fallback-ab
				   optional string, either true or false
       Rebalancing Configuration:
	  other_config : bond-rebalance-interval
				   optional string, containing	an  integer,  in
				   range 0 to 2,147,483,647
       bond_fake_iface		   boolean
     Spanning Tree Protocol:
       STP Configuration:
	  other_config : stp-enable
				   optional string, either true or false
	  other_config : stp-port-num
				   optional  string,  containing  an integer, in
				   range 1 to 255
	  other_config : stp-port-priority
				   optional string, containing	an  integer,  in
				   range 0 to 255
	  other_config : stp-path-cost
				   optional  string,  containing  an integer, in
				   range 0 to 65,535
       STP Status:
	  status : stp_port_id	   optional string
	  status : stp_state	   optional string, one of  blocking,  disabled,
				   forwarding, learning, or listening
	  status : stp_sec_in_state
				   optional  string,  containing  an integer, at
				   least 0
	  status : stp_role	   optional string,  one  of  alternate,  desig-
				   nated, or root
     Rapid Spanning Tree Protocol:
       RSTP Configuration:
	  other_config : rstp-enable
				   optional string, either true or false
	  other_config : rstp-port-priority
				   optional  string,  containing  an integer, in
				   range 0 to 240
	  other_config : rstp-port-num
				   optional string, containing	an  integer,  in
				   range 1 to 4,095
	  other_config : rstp-path-cost
				   optional string, containing an integer
	  other_config : rstp-port-admin-edge
				   optional string, either true or false
	  other_config : rstp-port-auto-edge
				   optional string, either true or false
	  other_config : rstp-port-mcheck
				   optional string, either true or false
       RSTP Status:
	  rstp_status : rstp_port_id
				   optional string
	  rstp_status : rstp_port_role
				   optional  string,  one  of Alternate, Backup,
				   Designated, Disabled, or Root
	  rstp_status : rstp_port_state
				   optional string, one of Disabled, Discarding,
				   Forwarding, or Learning
	  rstp_status : rstp_designated_bridge_id
				   optional string
	  rstp_status : rstp_designated_port_id
				   optional string
	  rstp_status : rstp_designated_path_cost
				   optional string, containing an integer
       RSTP Statistics:
	  rstp_statistics : rstp_tx_count
				   optional integer
	  rstp_statistics : rstp_rx_count
				   optional integer
	  rstp_statistics : rstp_error_count
				   optional integer
	  rstp_statistics : rstp_uptime
				   optional integer
     Multicast Snooping:
       other_config : mcast-snooping-flood
				   optional string, either true or false
       other_config : mcast-snooping-flood-reports
				   optional string, either true or false
     Other Features:
       qos			   optional QoS
       mac			   optional string
       fake_bridge		   boolean
       protected		   boolean
       external_ids : fake-bridge-id-*
				   optional string
       other_config : transient    optional string, either true or false
     bond_active_slave		   optional string
     Port Statistics:
       Statistics: STP transmit and receive counters:
	  statistics : stp_tx_count
				   optional integer
	  statistics : stp_rx_count
				   optional integer
	  statistics : stp_error_count
				   optional integer
     Common Columns:
       other_config		   map of string-string pairs
       external_ids		   map of string-string pairs

   Details:
     name: immutable string (must be unique within table)
	    Port name. For a non-bonded port, this should be the same as its in-
	    terface's name. Port names must otherwise be unique among the  names
	    of ports, interfaces, and bridges on a host. Because port and inter-
	    faces  names are usually the same, the restrictions on the name col-
	    umn in the Interface table, particularly on length,  also  apply  to
	    port  names.  Refer to the documentation for Interface names for de-
	    tails.

     interfaces: set of 1 or more Interfaces
	    The port's interfaces. If there is more than one, this is  a  bonded
	    Port.

   VLAN Configuration:

     In short, a VLAN (short for ``virtual LAN'') is a way to partition a single
     switch  into multiple switches. VLANs can be confusing, so for an introduc-
     tion, please refer to the question ``What's a VLAN?'' in the  Open  vSwitch
     FAQ.

     A	VLAN  is  sometimes encoded into a packet using a 802.1Q or 802.1ad VLAN
     header, but every packet is part of some VLAN whether or not it is  encoded
     in the packet. (A packet that appears to have no VLAN is part of VLAN 0, by
     default.)	As  a result, it's useful to think of a VLAN as a metadata prop-
     erty of a packet, separate from how the VLAN is encoded. For a given  port,
     this  column  determines  how  the  encoding  of a packet that ingresses or
     egresses the port maps to the packet's  VLAN.  When  a  packet  enters  the
     switch,  its VLAN is determined based on its setting in this column and its
     VLAN headers, if any, and then, conceptually, the	VLAN  headers  are  then
     stripped  off. Conversely, when a packet exits the switch, its VLAN and the
     settings in this column determine what VLAN headers,  if  any,  are  pushed
     onto the packet before it egresses the port.

     The  VLAN configuration in this column affects Open vSwitch only when it is
     doing ``normal switching.'' It does not affect flows set up by an	OpenFlow
     controller, outside of the OpenFlow ``normal action.''

     Bridge ports support the following types of VLAN configuration:

	    trunk  A  trunk  port carries packets on one or more specified VLANs
		   specified in the trunks column  (often,  on	every  VLAN).  A
		   packet  that  ingresses on a trunk port is in the VLAN speci-
		   fied in its 802.1Q header, or VLAN 0 if  the  packet  has  no
		   802.1Q  header.  A  packet that egresses through a trunk port
		   will have an 802.1Q header if it has a nonzero VLAN ID.

		   Any packet that ingresses on a trunk port tagged with a  VLAN
		   that the port does not trunk is dropped.

	    access
		   An  access port carries packets on exactly one VLAN specified
		   in the tag column. Packets egressing on an access  port  have
		   no 802.1Q header.

		   Any	packet with an 802.1Q header with a nonzero VLAN ID that
		   ingresses on an access port is dropped, regardless of whether
		   the VLAN ID in the header is the access port's VLAN ID.

	    native-tagged
		   A native-tagged port resembles a trunk port, with the  excep-
		   tion that a packet without an 802.1Q header that ingresses on
		   a  native-tagged port is in the ``native VLAN'' (specified in
		   the tag column).

	    native-untagged
		   A native-untagged port resembles a native-tagged  port,  with
		   the	exception  that  a  packet that egresses on a native-un-
		   tagged port in the  native  VLAN  will  not	have  an  802.1Q
		   header.

	    dot1q-tunnel
		   A  dot1q-tunnel port is somewhat like an access port. Like an
		   access port, it carries packets on the single VLAN  specified
		   in  the  tag  column  and this VLAN, called the service VLAN,
		   does not appear in an 802.1Q header for packets that  ingress
		   or egress on the port. The main difference lies in the behav-
		   ior	when packets that include a 802.1Q header ingress on the
		   port. Whereas an access port drops such packets, a dot1q-tun-
		   nel port treats these as double-tagged with the outer service
		   VLAN tag and the inner customer VLAN taken  from  the  802.1Q
		   header.  Correspondingly,  to  egress  on  the port, a packet
		   outer VLAN (or only VLAN) must be tag, which is  removed  be-
		   fore  egress,  which exposes the inner (customer) VLAN if one
		   is present.

		   If cvlans is set, only allows packets in the  specified  cus-
		   tomer VLANs.

     A	packet	will only egress through bridge ports that carry the VLAN of the
     packet, as described by the rules above.

     vlan_mode: optional string, one of access, dot1q-tunnel, native-tagged, na-
     tive-untagged, or trunk
	    The VLAN mode of the port, as described above. When this  column  is
	    empty, a default mode is selected as follows:

	    *	   If  tag  contains  a  value,  the port is an access port. The
		   trunks column should be empty.

	    *	   Otherwise, the port is a trunk port. The trunks column  value
		   is honored if it is present.

     tag: optional integer, in range 0 to 4,095
	    For an access port, the port's implicitly tagged VLAN. For a native-
	    tagged  or	native-untagged  port,	the  port's native VLAN. Must be
	    empty if this is a trunk port.

     trunks: set of up to 4,096 integers, in range 0 to 4,095
	    For a trunk, native-tagged, or native-untagged port, the 802.1Q VLAN
	    or VLANs that this port trunks; if it is empty, then the port trunks
	    all VLANs. Must be empty if this is an access port.

	    A native-tagged or native-untagged port  always  trunks  its  native
	    VLAN, regardless of whether trunks includes that VLAN.

     cvlans: set of up to 4,096 integers, in range 0 to 4,095
	    For a dot1q-tunnel port, the customer VLANs that this port includes.
	    If this is empty, the port includes all customer VLANs.

	    For other kinds of ports, this setting is ignored.

     other_config : qinq-ethtype: optional string, either 802.1ad or 802.1q
	    For  a dot1q-tunnel port, this is the TPID for the service tag, that
	    is, for the 802.1Q header that contains the service VLAN ID. Because
	    packets that actually ingress and egress a dot1q-tunnel port do  not
	    include  an 802.1Q header for the service VLAN, this does not affect
	    packets on the dot1q-tunnel port itself. Rather, it  determines  the
	    service  VLAN for a packet that ingresses on a dot1q-tunnel port and
	    egresses on a trunk port.

	    The value 802.1ad specifies TPID 0x88a8, which is also  the  default
	    if the setting is omitted. The value 802.1q specifies TPID 0x8100.

	    For other kinds of ports, this setting is ignored.

     other_config : priority-tags: optional string, one of always, if-nonzero,
     or never
	    An	802.1Q	header	contains  two important pieces of information: a
	    VLAN ID and a priority. A frame with a zero VLAN ID, called a ``pri-
	    ority-tagged'' frame, is supposed to be treated the same  way  as  a
	    frame without an 802.1Q header at all (except for the priority).

	    However,  some  network  elements  ignore  any frame that has 802.1Q
	    header at all, even when the VLAN ID is zero. Therefore, by  default
	    Open  vSwitch  does not output priority-tagged frames, instead omit-
	    ting the 802.1Q header entirely if the VLAN ID is zero. Set this key
	    to if-nonzero to enable priority-tagged frames on a port.

	    For if-nonzero Open vSwitch omits the 802.1Q  header  on  output  if
	    both the VLAN ID and priority would be zero. Set to always to retain
	    the 802.1Q header in such frames as well.

	    All  frames output to native-tagged ports have a nonzero VLAN ID, so
	    this setting is not meaningful on native-tagged ports.

   Bonding Configuration:

     A port that has more than one interface is a ``bonded port.''  Bonding  al-
     lows for load balancing and fail-over.

     The  following types of bonding will work with any kind of upstream switch.
     On the upstream switch, do not configure the interfaces as a bond:

	    balance-slb
		   Balances flows among members based on source MAC address  and
		   output  VLAN,  with	periodic rebalancing as traffic patterns
		   change.

	    active-backup
		   Assigns all flows to one member, failing  over  to  a  backup
		   member  when  the active member is disabled. This is the only
		   bonding mode in which interfaces may be plugged into  differ-
		   ent upstream switches.

     The  following  modes  require  the upstream switch to support 802.3ad with
     successful LACP negotiation.  If  LACP  negotiation  fails  and  other-con-
     fig:lacp-fallback-ab is true, then active-backup mode is used:

	    balance-tcp
		   Balances  flows among members based on L3 and L4 protocol in-
		   formation such as IP addresses and TCP/UDP ports.

     These columns apply only to bonded ports. Their values  are  otherwise  ig-
     nored.

     bond_mode: optional string, one of active-backup, balance-slb, or bal-
     ance-tcp
	    The  type  of  bonding  used  for  a  bonded  port.  Defaults to ac-
	    tive-backup if unset.

     other_config : bond-hash-basis: optional string, containing an integer
	    An integer hashed along with flows when choosing output  members  in
	    load  balanced  bonds. When changed, all flows will be assigned dif-
	    ferent hash values possibly causing member	selection  decisions  to
	    change.  Does not affect bonding modes which do not employ load bal-
	    ancing such as active-backup.

     other_config : lb-output-action: optional string, either true or false
	    Enable/disable usage of optimized  lb_output  action  for  balancing
	    flows  among  output  members in load balanced bonds in balance-tcp.
	    When enabled, it uses optimized path for balance-tcp mode  by  using
	    rss  hash  and avoids recirculation. This knob does not affect other
	    balancing modes.

     other_config : bond-primary: optional string
	    If a slave interface with this name exists in the bond and is up, it
	    will be made active. Relevant only	when  other_config:bond_mode  is
	    active-backup  or  if balance-tcp falls back to active-backup (e.g.,
	    LACP negotiation fails and other_config:lacp-fallback-ab is true).

   Link Failure Detection:

     An important part of link bonding is detecting that links are down so  that
     they  may	be  disabled.  These settings determine how Open vSwitch detects
     link failure.

     other_config : bond-detect-mode: optional string, either carrier or miimon
	    The means used to detect link failures. Defaults  to  carrier  which
	    uses  each	interface's  carrier to detect failures. When set to mi-
	    imon, will check for failures by polling each interface's MII.

     other_config : bond-miimon-interval: optional string, containing an integer
	    The interval, in milliseconds, between successive attempts	to  poll
	    each  interface's  MII. Relevant only when other_config:bond-detect-
	    mode is miimon.

     bond_updelay: integer
	    The number of milliseconds for which the link must stay up on an in-
	    terface before the interface is considered to be up.  Specify  0  to
	    enable the interface immediately.

	    This  setting  is honored only when at least one bonded interface is
	    already enabled. When no interfaces are enabled, then the first bond
	    interface to come up is enabled immediately.

     bond_downdelay: integer
	    The number of milliseconds for which the link must stay down  on  an
	    interface  before  the interface is considered to be down. Specify 0
	    to disable the interface immediately.

   LACP Configuration:

     LACP, the Link Aggregation Control Protocol, is an IEEE standard  that  al-
     lows  switches  to automatically detect that they are connected by multiple
     links and aggregate across those links. These settings control LACP  behav-
     ior.

     lacp: optional string, one of active, off, or passive
	    Configures	LACP  on  this	port.  LACP  allows  directly  connected
	    switches to negotiate which links may be bonded. LACP may be enabled
	    on non-bonded ports for the benefit of any switches they may be con-
	    nected to. active ports are allowed to initiate  LACP  negotiations.
	    passive ports are allowed to participate in LACP negotiations initi-
	    ated  by  a remote switch, but not allowed to initiate such negotia-
	    tions themselves. If LACP is enabled on a port whose partner  switch
	    does  not support LACP, the bond will be disabled, unless other-con-
	    fig:lacp-fallback-ab is set to true. Defaults to off if unset.

     other_config : lacp-system-id: optional string
	    The LACP system ID of this Port. The system ID of  a  LACP	bond  is
	    used  to  identify itself to its partners. Must be a nonzero MAC ad-
	    dress. Defaults to the bridge Ethernet address if unset.

     other_config : lacp-system-priority: optional string, containing an inte-
     ger, in range 1 to 65,535
	    The LACP system priority of this Port. In  LACP  negotiations,  link
	    status  decisions  are made by the system with the numerically lower
	    priority.

     other_config : lacp-time: optional string, either fast or slow
	    The LACP timing which should be used on this Port. By  default  slow
	    is used. When configured to be fast LACP heartbeats are requested at
	    a  rate  of  once per second causing connectivity problems to be de-
	    tected more quickly. In slow mode, heartbeats  are	requested  at  a
	    rate of once every 30 seconds.

     other_config : lacp-fallback-ab: optional string, either true or false
	    Determines	the  behavior  of  openvswitch bond in LACP mode. If the
	    partner switch does not support LACP, setting this	option	to  true
	    allows  openvswitch  to  fallback to active-backup. If the option is
	    set to false, the bond will be disabled. In both the cases, once the
	    partner switch is configured to LACP mode, the bond will use LACP.

   Rebalancing Configuration:

     These settings control behavior when a  bond  is  in  balance-slb	or  bal-
     ance-tcp mode.

     other_config : bond-rebalance-interval: optional string, containing an in-
     teger, in range 0 to 2,147,483,647
	    For  a load balanced bonded port, the number of milliseconds between
	    successive attempts to rebalance the bond, that is,  to  move  flows
	    from  one interface on the bond to another in an attempt to keep us-
	    age of each interface roughly equal. If zero, load balancing is dis-
	    abled on the bond (link failure still cause flows to move). If  less
	    than 1000ms, the rebalance interval will be 1000ms.

     bond_fake_iface: boolean
	    For  a bonded port, whether to create a fake internal interface with
	    the name of the port. Use only for compatibility with  legacy  soft-
	    ware that requires this.

   Spanning Tree Protocol:

     The  configuration  here  is  only meaningful, and the status is only popu-
     lated, when 802.1D-1998 Spanning Tree Protocol is	enabled  on  the  port's
     Bridge with its stp_enable column.

   STP Configuration:

     other_config : stp-enable: optional string, either true or false
	    When  STP is enabled on a bridge, it is enabled by default on all of
	    the bridge's ports except bond, internal, and mirror ports (which do
	    not work with STP). If this column's value is false, STP is disabled
	    on the port.

     other_config : stp-port-num: optional string, containing an integer, in
     range 1 to 255
	    The port number used for the lower 8 bits of  the  port-id.  By  de-
	    fault,  the  numbers  will	be assigned automatically. If any port's
	    number is manually configured on a bridge, then they must all be.

     other_config : stp-port-priority: optional string, containing an integer,
     in range 0 to 255
	    The port's relative priority value for  determining  the  root  port
	    (the  upper 8 bits of the port-id). A port with a lower port-id will
	    be chosen as the root port. By default, the priority is 0x80.

     other_config : stp-path-cost: optional string, containing an integer, in
     range 0 to 65,535
	    Spanning tree path cost for the port. A  lower  number  indicates  a
	    faster  link.  By default, the cost is based on the maximum speed of
	    the link.

   STP Status:

     status : stp_port_id: optional string
	    The port ID used in spanning tree advertisements for this port, as 4
	    hex digits. Configuring the port ID is described in the stp-port-num
	    and stp-port-priority keys of the other_config section earlier.

     status : stp_state: optional string, one of blocking, disabled, forwarding,
     learning, or listening
	    STP state of the port.

     status : stp_sec_in_state: optional string, containing an integer, at least
     0
	    The amount of time this port has been in the current STP  state,  in
	    seconds.

     status : stp_role: optional string, one of alternate, designated, or root
	    STP role of the port.

   Rapid Spanning Tree Protocol:

     The  configuration  here  is only meaningful, and the status and statistics
     are only populated, when 802.1D-1998 Spanning Tree Protocol is  enabled  on
     the port's Bridge with its stp_enable column.

   RSTP Configuration:

     other_config : rstp-enable: optional string, either true or false
	    When RSTP is enabled on a bridge, it is enabled by default on all of
	    the bridge's ports except bond, internal, and mirror ports (which do
	    not  work  with RSTP). If this column's value is false, RSTP is dis-
	    abled on the port.

     other_config : rstp-port-priority: optional string, containing an integer,
     in range 0 to 240
	    The port's relative priority value for determining the root port, in
	    multiples of 16. By default, the port priority is  0x80  (128).  Any
	    value  in  the  lower 4 bits is rounded off. The significant upper 4
	    bits become the upper 4 bits of the port-id. A port with the  lowest
	    port-id is elected as the root.

     other_config : rstp-port-num: optional string, containing an integer, in
     range 1 to 4,095
	    The  local	RSTP port number, used as the lower 12 bits of the port-
	    id. By default the port numbers are assigned automatically, and typ-
	    ically may not correspond to the OpenFlow port numbers. A port  with
	    the lowest port-id is elected as the root.

     other_config : rstp-path-cost: optional string, containing an integer
	    The  port  path  cost.  The Port's contribution, when it is the Root
	    Port, to the Root Path Cost for the Bridge. By default the	cost  is
	    automatically calculated from the port's speed.

     other_config : rstp-port-admin-edge: optional string, either true or false
	    The admin edge port parameter for the Port. Default is false.

     other_config : rstp-port-auto-edge: optional string, either true or false
	    The auto edge port parameter for the Port. Default is true.

     other_config : rstp-port-mcheck: optional string, either true or false
	    The mcheck port parameter for the Port. Default is false. May be set
	    to	force  the Port Protocol Migration state machine to transmit RST
	    BPDUs for a MigrateTime period, to test whether all STP  Bridges  on
	    the  attached  LAN	have  been  removed and the Port can continue to
	    transmit RSTP BPDUs. Setting mcheck has no effect if the  Bridge  is
	    operating in STP Compatibility mode.

	    Changing the value from true to false has no effect, but needs to be
	    done  if  this  behavior  is  to  be triggered again by subsequently
	    changing the value from false to true.

   RSTP Status:

     rstp_status : rstp_port_id: optional string
	    The port ID used in spanning tree advertisements for this port, as 4
	    hex  digits.  Configuring  the  port  ID   is   described	in   the
	    rstp-port-num  and	rstp-port-priority keys of the other_config sec-
	    tion earlier.

     rstp_status : rstp_port_role: optional string, one of Alternate, Backup,
     Designated, Disabled, or Root
	    RSTP role of the port.

     rstp_status : rstp_port_state: optional string, one of Disabled, Discard-
     ing, Forwarding, or Learning
	    RSTP state of the port.

     rstp_status : rstp_designated_bridge_id: optional string
	    The port's RSTP designated bridge ID, in the same form as  rstp_sta-
	    tus:rstp_bridge_id in the Bridge table.

     rstp_status : rstp_designated_port_id: optional string
	    The port's RSTP designated port ID, as 4 hex digits.

     rstp_status : rstp_designated_path_cost: optional string, containing an in-
     teger
	    The port's RSTP designated path cost. Lower is better.

   RSTP Statistics:

     rstp_statistics : rstp_tx_count: optional integer
	    Number of RSTP BPDUs transmitted through this port.

     rstp_statistics : rstp_rx_count: optional integer
	    Number of valid RSTP BPDUs received by this port.

     rstp_statistics : rstp_error_count: optional integer
	    Number of invalid RSTP BPDUs received by this port.

     rstp_statistics : rstp_uptime: optional integer
	    The duration covered by the other RSTP statistics, in seconds.

   Multicast Snooping:

     other_config : mcast-snooping-flood: optional string, either true or false
	    If	set to true, multicast packets (except Reports) are uncondition-
	    ally forwarded to the specific port.

     other_config : mcast-snooping-flood-reports: optional string, either true
     or false
	    If set to true, multicast Reports are unconditionally  forwarded  to
	    the specific port.

   Other Features:

     qos: optional QoS
	    Quality of Service configuration for this port.

     mac: optional string
	    The MAC address to use for this port for the purpose of choosing the
	    bridge's  MAC  address. This column does not necessarily reflect the
	    port's actual MAC address, nor will setting it change the port's ac-
	    tual MAC address.

     fake_bridge: boolean
	    Does this port represent a sub-bridge for its tagged VLAN within the
	    Bridge? See ovs-vsctl(8) for more information.

     protected: boolean
	    The protected ports feature allows certain ports to be designated as
	    protected. Traffic between protected  ports  is  blocked.  Protected
	    ports  can	send traffic to unprotected ports. Unprotected ports can
	    send traffic to any port. Default is false.

     external_ids : fake-bridge-id-*: optional string
	    External IDs for a fake bridge (see the fake_bridge column) are  de-
	    fined by prefixing a Bridge external_ids key with fake-bridge-, e.g.
	    fake-bridge-xs-network-uuids.

     other_config : transient: optional string, either true or false
	    If	set  to  true,	the  port  will  be  removed  when ovs-ctl start
	    --delete-transient-ports is used.

     bond_active_slave: optional string
	    For a bonded port, record the MAC address of the current active mem-
	    ber.

   Port Statistics:

     Key-value pairs that report port statistics.  The	update	period	is  con-
     trolled by other_config:stats-update-interval in the Open_vSwitch table.

   Statistics: STP transmit and receive counters:

     statistics : stp_tx_count: optional integer
	    Number of STP BPDUs sent on this port by the spanning tree library.

     statistics : stp_rx_count: optional integer
	    Number  of STP BPDUs received on this port and accepted by the span-
	    ning tree library.

     statistics : stp_error_count: optional integer
	    Number of bad STP BPDUs received on this  port.  Bad  BPDUs  include
	    runt packets and those with an unexpected protocol ID.

   Common Columns:

     The  overall  purpose of these columns is described under Common Columns at
     the beginning of this document.

     other_config: map of string-string pairs

     external_ids: map of string-string pairs

Interface TABLE
     An interface within a Port.

   Summary:
     Core Features:
       name			   immutable string (must be unique  within  ta-
				   ble)
       ifindex			   optional integer, in range 0 to 4,294,967,295
       mac_in_use		   optional string
       mac			   optional string
       error			   optional string
       OpenFlow Port Number:
	  ofport		   optional integer
	  ofport_request	   optional integer, in range 1 to 65,279
     System-Specific Details:
       type			   string
     Tunnel Options:
       options : remote_ip	   optional string
       options : local_ip	   optional string
       options : in_key 	   optional string
       options : out_key	   optional string
       options : dst_port	   optional string
       options : key		   optional string
       options : tos		   optional string
       options : ttl		   optional string
       options : df_default	   optional string, either true or false
       options : egress_pkt_mark   optional string
       Tunnel Options: lisp only:
	  options : packet_type    optional string, either legacy_l3 or ptap
       Tunnel Options: vxlan only:
	  options : exts	   optional string
	  options : packet_type    optional string, one of legacy_l2, legacy_l3,
				   or ptap
       Tunnel Options: gre only:
	  options : packet_type    optional string, one of legacy_l2, legacy_l3,
				   or ptap
	  options : seq 	   optional string, either true or false
       Tunnel Options: gre, ip6gre, geneve, bareudp and vxlan:
	  options : csum	   optional string, either true or false
       Tunnel Options: IPsec:
	  options : psk 	   optional string
	  options : remote_cert    optional string
	  options : remote_name    optional string
     Tunnel Options: erspan only:
       options : erspan_idx	   optional string
       options : erspan_ver	   optional string
       options : erspan_dir	   optional string
       options : erspan_hwid	   optional string
     Tunnel Options: Bareudp only:
       options : payload_type	   optional string
     Patch Options:
       options : peer		   optional string
     PMD (Poll Mode Driver) Options:
       options : n_rxq		   optional  string,  containing  an integer, at
				   least 1
       options : dpdk-devargs	   optional string
       other_config : pmd-rxq-affinity
				   optional string
       options : xdp-mode	   optional string, one of best-effort, generic,
				   native-with-zerocopy, or native
       options : use-need-wakeup   optional string, either true or false
       options : vhost-server-path
				   optional string
       options : tx-retries-max    optional string, containing	an  integer,  in
				   range 0 to 32
       options : n_rxq_desc	   optional  string,  containing  an integer, in
				   range 1 to 4,096
       options : n_txq_desc	   optional string, containing	an  integer,  in
				   range 1 to 4,096
       options : dpdk-vf-mac	   optional string
       other_config : tx-steering
				   optional string, either hash or thread
     EMC (Exact Match Cache) Configuration:
       other_config : emc-enable   optional string, either true or false
     MTU:
       mtu			   optional integer
       mtu_request		   optional integer, at least 1
     Interface Status:
       admin_state		   optional string, either down or up
       link_state		   optional string, either down or up
       link_resets		   optional integer
       link_speed		   optional integer
       duplex			   optional string, either full or half
       lacp_current		   optional boolean
       status			   map of string-string pairs
       status : driver_name	   optional string
       status : driver_version	   optional string
       status : firmware_version   optional string
       status : source_ip	   optional string
       status : tunnel_egress_iface
				   optional string
       status : tunnel_egress_iface_carrier
				   optional string, either down or up
       dpdk:
	  status : port_no	   optional string
	  status : numa_id	   optional string
	  status : min_rx_bufsize  optional string
	  status : max_rx_pktlen   optional string
	  status : max_rx_queues   optional string
	  status : max_tx_queues   optional string
	  status : max_mac_addrs   optional string
	  status : max_hash_mac_addrs
				   optional string
	  status : max_vfs	   optional string
	  status : max_vmdq_pools  optional string
	  status : if_type	   optional string
	  status : if_descr	   optional string
	  status : pci-vendor_id   optional string
	  status : pci-device_id   optional string
	  status : dpdk-vf-mac	   optional string
       dpdkvhostuser:
	  status : mode 	   optional string
	  status : features	   optional string
	  status : num_of_vrings   optional string
	  status : numa 	   optional string
	  status : socket	   optional string
	  status : status	   optional string
	  status : vring_n_size    optional string
	  status : userspace-tso   optional string
     Statistics:
       Statistics: Successful transmit and receive counters:
	  statistics : rx_packets  optional integer
	  statistics : rx_bytes    optional integer
	  statistics : tx_packets  optional integer
	  statistics : tx_bytes    optional integer
       Statistics: Receive errors:
	  statistics : rx_dropped  optional integer
	  statistics : rx_frame_err
				   optional integer
	  statistics : rx_over_err
				   optional integer
	  statistics : rx_crc_err  optional integer
	  statistics : rx_errors   optional integer
       Statistics: Transmit errors:
	  statistics : tx_dropped  optional integer
	  statistics : collisions  optional integer
	  statistics : tx_errors   optional integer
     Ingress Policing:
       ingress_policing_rate	   integer, at least 0
       ingress_policing_kpkts_rate
				   integer, at least 0
       ingress_policing_burst	   integer, at least 0
       ingress_policing_kpkts_burst
				   integer, at least 0
     Bidirectional Forwarding Detection (BFD):
       BFD Configuration:
	  bfd : enable		   optional string, either true or false
	  bfd : min_rx		   optional  string,  containing  an integer, at
				   least 1
	  bfd : min_tx		   optional string, containing	an  integer,  at
				   least 1
	  bfd : decay_min_rx	   optional string, containing an integer
	  bfd : forwarding_if_rx   optional string, either true or false
	  bfd : cpath_down	   optional string, either true or false
	  bfd : check_tnl_key	   optional string, either true or false
	  bfd : bfd_local_src_mac  optional string
	  bfd : bfd_local_dst_mac  optional string
	  bfd : bfd_remote_dst_mac
				   optional string
	  bfd : bfd_src_ip	   optional string
	  bfd : bfd_dst_ip	   optional string
	  bfd : oam		   optional string
	  bfd : mult		   optional  string,  containing  an integer, in
				   range 1 to 255
       BFD Status:
	  bfd_status : state	   optional string,  one  of  admin_down,  down,
				   init, or up
	  bfd_status : forwarding  optional string, either true or false
	  bfd_status : diagnostic  optional string
	  bfd_status : remote_state
				   optional  string,  one  of  admin_down, down,
				   init, or up
	  bfd_status : remote_diagnostic
				   optional string
	  bfd_status : flap_count  optional string, containing	an  integer,  at
				   least 0
     Connectivity Fault Management:
       cfm_mpid 		   optional integer
       cfm_flap_count		   optional integer
       cfm_fault		   optional boolean
       cfm_fault_status : recv	   none
       cfm_fault_status : rdi	   none
       cfm_fault_status : maid	   none
       cfm_fault_status : loopback
				   none
       cfm_fault_status : overflow
				   none
       cfm_fault_status : override
				   none
       cfm_fault_status : interval
				   none
       cfm_remote_opstate	   optional string, either down or up
       cfm_health		   optional integer, in range 0 to 100
       cfm_remote_mpids 	   set of integers
       other_config : cfm_interval
				   optional string, containing an integer
       other_config : cfm_extended
				   optional string, either true or false
       other_config : cfm_demand   optional string, either true or false
       other_config : cfm_opstate
				   optional string, either down or up
       other_config : cfm_ccm_vlan
				   optional  string,  containing  an integer, in
				   range 1 to 4,095
       other_config : cfm_ccm_pcp
				   optional string, containing	an  integer,  in
				   range 1 to 7
     Bonding Configuration:
       other_config : lacp-port-id
				   optional  string,  containing  an integer, in
				   range 1 to 65,535
       other_config : lacp-port-priority
				   optional string, containing	an  integer,  in
				   range 1 to 65,535
       other_config : lacp-aggregation-key
				   optional  string,  containing  an integer, in
				   range 1 to 65,535
     Virtual Machine Identifiers:
       external_ids : attached-mac
				   optional string
       external_ids : iface-id	   optional string
       external_ids : iface-status
				   optional string, either active or inactive
       external_ids : xs-vif-uuid
				   optional string
       external_ids : xs-network-uuid
				   optional string
       external_ids : vm-id	   optional string
       external_ids : xs-vm-uuid   optional string
     Auto Attach Configuration:
       lldp : enable		   optional string, either true or false
     Flow control Configuration:
       options : rx-flow-ctrl	   optional string, either true or false
       options : tx-flow-ctrl	   optional string, either true or false
       options : flow-ctrl-autoneg
				   optional string, either true or false
     Link State Change detection mode:
       options : dpdk-lsc-interrupt
				   optional string, either true or false
     Common Columns:
       other_config		   map of string-string pairs
       external_ids		   map of string-string pairs

   Details:
   Core Features:

     name: immutable string (must be unique within table)
	    Interface name. Should be alphanumeric. For  non-bonded  port,  this
	    should  be	the  same  as the port name. It must otherwise be unique
	    among the names of ports, interfaces, and bridges on a host.

	    The maximum length of an interface name depends  on  the  underlying
	    datapath:

	    *	   The	names of interfaces implemented as Linux and BSD network
		   devices, including interfaces with  type  internal,	tap,  or
		   system  plus the different types of tunnel ports, are limited
		   to 15 bytes. Windows limits these names to 255 bytes.

	    *	   The names of patch ports are not used in the underlying data-
		   path, so operating system restrictions do  not  apply.  Thus,
		   they may have arbitrary length.

	    Regardless	of  other  restrictions,  OpenFlow only supports 15-byte
	    names, which means that ovs-ofctl and OpenFlow controllers will show
	    names truncated to 15 bytes.

     ifindex: optional integer, in range 0 to 4,294,967,295
	    A positive interface index as defined for SNMP MIB-II in  RFCs  1213
	    and 2863, if the interface has one, otherwise 0. The ifindex is use-
	    ful for seamless integration with protocols such as SNMP and sFlow.

     mac_in_use: optional string
	    The MAC address in use by this interface.

     mac: optional string
	    Ethernet  address  to  set for this interface. If unset then the de-
	    fault MAC address is used:

	    *	   For the local interface, the default is  the  lowest-numbered
		   MAC address among the other bridge ports, either the value of
		   the	mac  in  its Port record, if set, or its actual MAC (for
		   bonded ports, the MAC of its member whose name  is  first  in
		   alphabetical order). Internal ports and bridge ports that are
		   used  as  port  mirroring destinations (see the Mirror table)
		   are ignored.

	    *	   For other internal interfaces, the default  MAC  is	randomly
		   generated.

	    *	   External  interfaces  typically have a MAC address associated
		   with their hardware.

	    Some interfaces may not have a  software-controllable  MAC	address.
	    This  option  only affects internal ports. For other type ports, you
	    can change the MAC address outside Open vSwitch, using ip command.

     error: optional string
	    If the configuration of the port failed, as indicated by -1  in  of-
	    port, Open vSwitch sets this column to an error description in human
	    readable form. Otherwise, Open vSwitch clears this column.

   OpenFlow Port Number:

     When  a  client adds a new interface, Open vSwitch chooses an OpenFlow port
     number for the new port. If the client that adds  the  port  fills  in  of-
     port_request, then Open vSwitch tries to use its value as the OpenFlow port
     number.  Otherwise,  or  if  the requested port number is already in use or
     cannot be used for another reason, Open  vSwitch  automatically  assigns  a
     free  port  number.  Regardless  of  how the port number was obtained, Open
     vSwitch then reports in ofport the port number actually assigned.

     Open vSwitch limits the port numbers that it automatically assigns  to  the
     range  1  through 32,767, inclusive. Controllers therefore have free use of
     ports 32,768 and up.

     ofport: optional integer
	    OpenFlow port number for this interface. Open vSwitch sets this col-
	    umn's value, so other clients should treat it as read-only.

	    The OpenFlow ``local'' port (OFPP_LOCAL) is 65,534. The other  valid
	    port numbers are in the range 1 to 65,279, inclusive. Value -1 indi-
	    cates an error adding the interface.

     ofport_request: optional integer, in range 1 to 65,279
	    Requested OpenFlow port number for this interface.

	    A client should ideally set this column's value in the same database
	    transaction  that it uses to create the interface. Open vSwitch ver-
	    sion 2.1 and later will honor a later request for  a  specific  port
	    number,  althuogh  it  might confuse some controllers: OpenFlow does
	    not have a way to announce a port number  change,  so  Open  vSwitch
	    represents	it over OpenFlow as a port deletion followed immediately
	    by a port addition.

	    If ofport_request is set or changed to some other  port's  automati-
	    cally  assigned  port number, Open vSwitch chooses a new port number
	    for the latter port.

   System-Specific Details:

     type: string
	    The interface type. The types supported by a particular instance  of
	    Open   vSwitch   are   listed  in  the  iface_types  column  in  the
	    Open_vSwitch table. The following types are defined:

	    system
		   An ordinary network device, e.g. eth0 on Linux. Sometimes re-
		   ferred to as ``external interfaces'' since they are generally
		   connected to hardware external to  that  on	which  the  Open
		   vSwitch is running. The empty string is a synonym for system.

	    internal
		   A  simulated  network device that sends and receives traffic.
		   An internal interface whose name is the same as its	bridge's
		   name  is  called  the  ``local  interface.'' It does not make
		   sense to bond an internal interface, so  the  terms	``port''
		   and ``interface'' are often used imprecisely for internal in-
		   terfaces.

	    tap    A TUN/TAP device managed by Open vSwitch.

		   Open  vSwitch  checks the interface state before send packets
		   to the device. When it is down, the packets are  dropped  and
		   the	tx_dropped  statistic is updated accordingly. Older ver-
		   sions of Open vSwitch did not check the interface  state  and
		   then the tx_packets was incremented along with tx_dropped.

	    geneve
		   An		   Ethernet		 over		  Geneve
		   (http://tools.ietf.org/html/draft-ietf-nvo3-geneve) IPv4/IPv6
		   tunnel. A description of how to match and set Geneve  options
		   can be found in the ovs-ofctl manual page.

	    gre    Generic Routing Encapsulation (GRE) over IPv4 tunnel, config-
		   urable to encapsulate layer 2 or layer 3 traffic.

	    ip6gre
		   Generic  Routing Encapsulation (GRE) over IPv6 tunnel, encap-
		   sulate layer 2 traffic.

	    vxlan  An Ethernet tunnel over  the  UDP-based  VXLAN  protocol  de-
		   scribed in RFC 7348.

		   Open  vSwitch  uses	IANA-assigned UDP destination port 4789.
		   The source port used for VXLAN traffic varies on  a	per-flow
		   basis and is in the ephemeral port range.

	    lisp   A  layer 3 tunnel over the experimental, UDP-based Locator/ID
		   Separation Protocol (RFC 6830).

		   Only IPv4 and IPv6 packets are supported by the protocol, and
		   they are sent and received without an Ethernet header.  Traf-
		   fic	to/from  LISP ports is expected to be configured explic-
		   itly, and the ports are not intended to participate in learn-
		   ing based switching. As such, they are always  excluded  from
		   packet flooding.

	    stt    The	Stateless  TCP	Tunnel (STT) is particularly useful when
		   tunnel endpoints are in end-systems, as it utilizes the capa-
		   bilities of standard network interface cards to improve  per-
		   formance.  STT  utilizes  a	TCP-like  header  inside  the IP
		   header. It is stateless, i.e., there  is  no  TCP  connection
		   state  of  any  kind associated with the tunnel. The TCP-like
		   header is used to leverage the capabilities of existing  net-
		   work interface cards, but should not be interpreted as imply-
		   ing any sort of connection state between endpoints. Since the
		   STT	protocol  does	not  engage in the usual TCP 3-way hand-
		   shake, so it will have difficulty traversing  stateful  fire-
		   walls.      The	protocol      is      documented      at
		   https://tools.ietf.org/html/draft-davie-stt All traffic  uses
		   a default destination port of 7471.

	    patch  A pair of virtual devices that act as a patch cable.

	    gtpu   GPRS Tunneling Protocol (GTP) is a group of IP-based communi-
		   cations  protocols used to carry general packet radio service
		   (GPRS) within GSM, UMTS and LTE networks. GTP-U is  used  for
		   carrying  user  data within the GPRS core network and between
		   the radio access network and the core network. The user  data
		   transported	can be packets in any of IPv4, IPv6, or PPP for-
		   mats.

		   The protocol  is  documented  at  http://www.3gpp.org/DynaRe-
		   port/29281.htm

		   Open  vSwitch uses UDP destination port 2152. The source port
		   used for GTP traffic varies on a per-flow basis and is in the
		   ephemeral port range.

	    Bareudp
		   The Bareudp tunnel provides a generic L3  encapsulation  sup-
		   port for tunnelling different L3 protocols like MPLS, IP, NSH
		   etc. inside a UDP tunnel.

   Tunnel Options:

     These  options  apply  to	interfaces  with  type	of geneve, bareudp, gre,
     ip6gre, vxlan, lisp and stt.

     Each tunnel must be uniquely identified by the  combination  of  type,  op-
     tions:remote_ip, options:local_ip, and options:in_key. If two ports are de-
     fined that are the same except one has an optional identifier and the other
     does not, the more specific one is matched first. options:in_key is consid-
     ered  more specific than options:local_ip if a port defines one and another
     port defines the other. options:in_key is not applicable for  bareudp  tun-
     nels. Hence it is not considered while identifying a bareudp tunnel.

     options : remote_ip: optional string
	    Required. The remote tunnel endpoint, one of:

	    *	   An IPv4 or IPv6 address (not a DNS name), e.g. 192.168.0.123.
		   Only unicast endpoints are supported.

	    *	   The	word  flow.  The  tunnel accepts packets from any remote
		   tunnel endpoint. To process only packets from a specific  re-
		   mote  tunnel  endpoint,  the  flow  entries	may match on the
		   tun_src or tun_ipv6_srcfield. When sending packets to  a  re-
		   mote_ip=flow tunnel, the flow actions must explicitly set the
		   tun_dst  or	tun_ipv6_dst  field to the IP address of the de-
		   sired remote tunnel endpoint, e.g. with a set_field action.

	    The remote tunnel endpoint for any packet received from a tunnel  is
	    available in the tun_src field for matching in the flow table.

     options : local_ip: optional string
	    Optional.  The  tunnel  destination  IP  that  received packets must
	    match. Default is to match all addresses. If specified, may  be  one
	    of:

	    *	   An IPv4/IPv6 address (not a DNS name), e.g. 192.168.12.3.

	    *	   The	word flow. The tunnel accepts packets sent to any of the
		   local IP addresses of the system running OVS. To process only
		   packets sent to a specific IP address, the flow  entries  may
		   match  on  the  tun_dst  or	tun_ipv6_dst field. When sending
		   packets to a local_ip=flow tunnel, the flow actions	may  ex-
		   plicitly set the tun_src or tun_ipv6_src field to the desired
		   IP  address,  e.g.  with  a	set_field action. However, while
		   routing the tunneled packet out, the local system  may  over-
		   ride  the specified address with the local IP address config-
		   ured for the outgoing system interface.

		   This option is valid only for tunnels  also	configured  with
		   the remote_ip=flow option.

	    The  tunnel  destination  IP  address for any packet received from a
	    tunnel is available in the tun_dst or tun_ipv6_dst field for  match-
	    ing in the flow table.

     options : in_key: optional string
	    Optional,  not applicable for bareudp. The key that received packets
	    must contain, one of:

	    *	   0. The tunnel receives packets with no key or with a  key  of
		   0. This is equivalent to specifying no options:in_key at all.

	    *	   A  positive 24-bit (for Geneve, VXLAN, and LISP), 32-bit (for
		   GRE) or 64-bit (for STT) number.  The  tunnel  receives  only
		   packets with the specified key.

	    *	   The	word  flow. The tunnel accepts packets with any key. The
		   key will be placed in the tun_id field for  matching  in  the
		   flow table. The ovs-fields(7) manual page contains additional
		   information about matching fields in OpenFlow flows.

     options : out_key: optional string
	    Optional,  not applicable for bareudp. The key to be set on outgoing
	    packets, one of:

	    *	   0. Packets sent through the tunnel will have no key. This  is
		   equivalent to specifying no options:out_key at all.

	    *	   A  positive	24-bit (for Geneve, VXLAN and LISP), 32-bit (for
		   GRE) or 64-bit (for STT) number.  Packets  sent  through  the
		   tunnel will have the specified key.

	    *	   The	word flow. Packets sent through the tunnel will have the
		   key set using the set_tunnel Nicira OpenFlow vendor extension
		   (0 is used in the absence of an  action).  The  ovs-fields(7)
		   manual  page contains additional information about the Nicira
		   OpenFlow vendor extensions.

     options : dst_port: optional string
	    Optional. The tunnel transport layer destination port, for	UDP  and
	    TCP based tunnel protocols (Geneve, VXLAN, LISP, and STT).

     options : key: optional string
	    Optional. Shorthand to set in_key and out_key at the same time.

     options : tos: optional string
	    Optional.  The  value of the ToS bits to be set on the encapsulating
	    packet. ToS is interpreted as DSCP and ECN bits, ECN  part	must  be
	    zero. It may also be the word inherit, in which case the ToS will be
	    copied  from  the  inner  packet if it is IPv4 or IPv6 (otherwise it
	    will be 0). The ECN fields are always inherited. Default is 0.

     options : ttl: optional string
	    Optional. The TTL to be set on the encapsulating packet. It may also
	    be the word inherit, in which case the TTL will be copied  from  the
	    inner  packet if it is IPv4 or IPv6 (otherwise it will be the system
	    default, typically 64). Default is the system default TTL.

     options : df_default: optional string, either true or false
	    Optional. If enabled, the Don't Fragment bit will be set  on  tunnel
	    outer  headers  to allow path MTU discovery. Default is enabled; set
	    to false to disable.

     options : egress_pkt_mark: optional string
	    Optional. The pkt_mark to be set on the encapsulating  packet.  This
	    option sets packet mark for the tunnel endpoint for all tunnel pack-
	    ets including tunnel monitoring.

   Tunnel Options: lisp only:

     options : packet_type: optional string, either legacy_l3 or ptap
	    A  LISP  tunnel  sends and receives only IPv4 and IPv6 packets. This
	    option controls what how the tunnel represents the packets	that  it
	    sends and receives:

	    *	   By default, or if this option is legacy_l3, the tunnel repre-
		   sents  packets  as  Ethernet  frames  for  compatibility with
		   legacy OpenFlow controllers that expect this behavior.

	    *	   If this option is ptap, the tunnel represents  packets  using
		   the packet_type mechanism introduced in OpenFlow 1.5.

   Tunnel Options: vxlan only:

     options : exts: optional string
	    Optional.  Comma  separated list of optional VXLAN extensions to en-
	    able. The following extensions are supported:

	    *	   gbp: VXLAN-GBP allows to transport the group  policy  context
		   of  a  packet across the VXLAN tunnel to other network peers.
		   See	the  description  of  tun_gbp_id  and  tun_gbp_flags  in
		   ovs-fields(7)	for	   additional	    information.
		   (https://tools.ietf.org/html/draft-smith-vxlan-group-policy)

	    *	   gpe: Support for Generic Protocol Encapsulation in accordance
		   with 		       IETF			   draft
		   https://tools.ietf.org/html/draft-ietf-nvo3-vxlan-gpe.  With-
		   out this option, a VXLAN packet always encapsulates an Ether-
		   net frame. With this option, an VXLAN packet may also  encap-
		   sulate an IPv4, IPv6, NSH, or MPLS packet.

     options : packet_type: optional string, one of legacy_l2, legacy_l3, or
     ptap
	    This  option controls what types of packets the tunnel sends and re-
	    ceives and how it represents them:

	    *	   By default, or if this option is legacy_l2, the tunnel  sends
		   and receives only Ethernet frames.

	    *	   If  this  option  is legacy_l3, the tunnel sends and receives
		   only non-Ethernet (L3) packet, but  the  packets  are  repre-
		   sented as Ethernet frames for compatibility with legacy Open-
		   Flow controllers that expect this behavior. This requires en-
		   abling gpe in options:exts.

	    *	   If  this  option  is ptap, Open vSwitch represents packets in
		   the tunnel using  the  packet_type  mechanism  introduced  in
		   OpenFlow 1.5. This mechanism supports any kind of packet, but
		   actually  sending and receiving non-Ethernet packets requires
		   additionally enabling gpe in options:exts.

   Tunnel Options: gre only:

     gre interfaces support these options.

     options : packet_type: optional string, one of legacy_l2, legacy_l3, or
     ptap
	    This option controls what types of packets the tunnel sends and  re-
	    ceives and how it represents them:

	    *	   By  default, or if this option is legacy_l2, the tunnel sends
		   and receives only Ethernet frames.

	    *	   If this option is legacy_l3, the tunnel  sends  and	receives
		   only  non-Ethernet  (L3)  packet,  but the packets are repre-
		   sented as Ethernet frames for compatibility with legacy Open-
		   Flow controllers that expect this behavior.

	    *	   The legacy_l3 option is only available  via	the  user  space
		   datapath. The OVS kernel datapath does not support devices of
		   type ARPHRD_IPGRE which is the requirement for legacy_l3 type
		   packets.

	    *	   If  this  option  is  ptap, the tunnel sends and receives any
		   kind of packet. Open vSwitch represents packets in the tunnel
		   using the packet_type mechanism introduced in OpenFlow 1.5.

     options : seq: optional string, either true or false
	    Optional. A 4-byte sequence number field for GRE  tunnel  only.  De-
	    fault  is disabled, set to true to enable. Sequence number is incre-
	    mented by one on each outgoing packet.

   Tunnel Options: gre, ip6gre, geneve, bareudp and vxlan:

     gre, ip6gre, geneve, bareudp and vxlan interfaces support these options.

     options : csum: optional string, either true or false
	    Optional. Compute encapsulation header (either GRE or UDP) checksums
	    on outgoing packets. Default is disabled, set  to  true  to  enable.
	    Checksums  present	on incoming packets will be validated regardless
	    of this setting.

	    When using the upstream Linux kernel module, computation  of  check-
	    sums  for  geneve  and  vxlan  requires  Linux kernel version 4.0 or
	    higher. gre and ip6gre support checksums for all  versions	of  Open
	    vSwitch  that support GRE. The out of tree kernel module distributed
	    as part of OVS can compute all tunnel checksums on any  kernel  ver-
	    sion that it is compatible with.

   Tunnel Options: IPsec:

     Setting any of these options enables IPsec support for a given tunnel. gre,
     geneve,  vxlan and stt interfaces support these options. See the IPsec sec-
     tion in the Open_vSwitch table for a description of each mode.

     options : psk: optional string
	    In PSK mode only, the preshared secret  to	negotiate  tunnel.  This
	    value must match on both tunnel ends.

     options : remote_cert: optional string
	    In	self-signed certificate mode only, name of a PEM file containing
	    a certificate of the remote switch. The certificate  must  be  x.509
	    version  3	and  with the string in common name (CN) also set in the
	    subject alternative name (SAN).

     options : remote_name: optional string
	    In CA-signed certificate mode only, common name (CN) of  the  remote
	    certificate.

   Tunnel Options: erspan only:

     Only erspan interfaces support these options.

     options : erspan_idx: optional string
	    20 bit index/port number associated with the ERSPAN traffic's source
	    port  and  direction (ingress/egress). This field is platform depen-
	    dent.

     options : erspan_ver: optional string
	    ERSPAN version: 1 for version 1 (type II) or 2 for version	2  (type
	    III).

     options : erspan_dir: optional string
	    Specifies  the  ERSPAN v2 mirrored traffic's direction. 1 for egress
	    traffic, and 0 for ingress traffic.

     options : erspan_hwid: optional string
	    ERSPAN hardware ID is a 6-bit unique identifier of an ERSPAN v2  en-
	    gine within a system.

   Tunnel Options: Bareudp only:

     options : payload_type: optional string
	    Specifies  the  ethertype  of  the l3 protocol the bareudp device is
	    tunnelling. For the tunnels which supports multiple ethertypes of  a
	    l3	protocol  (IP, MPLS) this field specifies the protocol name as a
	    string.

   Patch Options:

     These options apply only to patch ports, that  is,  interfaces  whose  type
     column is patch. Patch ports are mainly a way to connect otherwise indepen-
     dent  bridges to one another, similar to how one might plug an Ethernet ca-
     ble (a ``patch  cable'')  into  two  physical  switches  to  connect  those
     switches.	The effect of plugging a patch port into two switches is concep-
     tually similar to that of plugging the two ends of a Linux veth device into
     those switches, but the implementation of patch ports makes them much  more
     efficient.

     Patch  ports may connect two different bridges (the usual case) or the same
     bridge. In the latter case, take special care to avoid loops, e.g. by  pro-
     gramming  appropriate  flows  with OpenFlow. Patch ports do not work if its
     ends are attached to  bridges  on	different  datapaths,  e.g.  to  connect
     bridges in system and netdev datapaths.

     The  following  command creates and connects patch ports p0 and p1 and adds
     them to bridges br0 and br1, respectively:

     ovs-vsctl add-port br0 p0 -- set Interface p0 type=patch options:peer=p1 \
	    -- add-port br1 p1 -- set Interface p1 type=patch options:peer=p0

     options : peer: optional string
	    The name of the Interface for the other side of the patch. The named
	    Interface's own peer option must specify this Interface's name. That
	    is, the two patch interfaces must have reversed name and  peer  val-
	    ues.

   PMD (Poll Mode Driver) Options:

     Only PMD netdevs support these options.

     options : n_rxq: optional string, containing an integer, at least 1
	    Specifies the maximum number of rx queues to be created for PMD net-
	    dev.  If  not specified or specified to 0, one rx queue will be cre-
	    ated by default. Not supported by DPDK vHost interfaces.

     options : dpdk-devargs: optional string
	    Specifies the PCI address associated with the port for physical  de-
	    vices,  or the virtual driver to be used for the port when a virtual
	    PMD is intended to be used. For the latter, the argument string typ-
	    ically takes the form of eth_driver_namex, where  driver_name  is  a
	    valid  virtual  DPDK PMD driver name and x is a unique identifier of
	    your choice for the given port. Only  supported  by  the  dpdk  port
	    type.

     other_config : pmd-rxq-affinity: optional string
	    Specifies mapping of RX queues of this interface to CPU cores.

	    Value should be set in the following form:

	    other_config:pmd-rxq-affinity=<rxq-affinity-list>

	    where

	    *	   <rxq-affinity-list> ::= NULL | <non-empty-list>

	    *	   <non-empty-list>  ::=  <affinity-pair>  |  <affinity-pair>  ,
		   <non-empty-list>

	    *	   <affinity-pair> ::= <queue-id> : <core-id>

     options : xdp-mode: optional string, one of best-effort, generic, na-
     tive-with-zerocopy, or native
	    Specifies the operational mode of the XDP program.

	    In native-with-zerocopy mode the XDP program is loaded into the  de-
	    vice driver with zero-copy RX and TX enabled. This mode requires de-
	    vice  driver  support  and	has  the  best performance because there
	    should be no copying of packets.

	    native is the same as native-with-zerocopy,  but  without  zero-copy
	    capability.  This  requires at least one copy between kernel and the
	    userspace. This mode also requires support from device driver.

	    In generic case the XDP program in kernel works after skb allocation
	    on early stages of packet processing inside the network stack.  This
	    mode doesn't require driver support, but has much lower performance.

	    best-effort  tries	to detect and choose the best (fastest) from the
	    available modes for current interface.

	    Note that this option  is  specific  to  netdev-afxdp.  Defaults  to
	    best-effort mode.

     options : use-need-wakeup: optional string, either true or false
	    Specifies whether to use need_wakeup feature in afxdp netdev. If en-
	    abled,  OVS  explicitly wakes up the kernel RX, using poll() syscall
	    and wakes up TX, using sendto() syscall. For physical devices,  this
	    feature  improves  the  performance  by  avoiding unnecessary sendto
	    syscalls. Defaults to true if supported by libbpf.

     options : vhost-server-path: optional string
	    The value specifies the path to the socket associated with	a  vHost
	    User  client  mode	device that has been or will be created by QEMU.
	    Only supported by dpdkvhostuserclient interfaces.

     options : tx-retries-max: optional string, containing an integer, in range
     0 to 32
	    The value specifies the maximum amount of vhost tx retries that  can
	    be	made  while  trying  to send a batch of packets to an interface.
	    Only supported by dpdkvhostuserclient interfaces.

	    Default value is 8.

     options : n_rxq_desc: optional string, containing an integer, in range 1 to
     4,096
	    Specifies the rx queue size (number rx descriptors) for dpdk  ports.
	    The  value must be a power of 2, less than 4096 and supported by the
	    hardware of the device being configured. If not specified or an  in-
	    correct  value is specified, 2048 rx descriptors will be used by de-
	    fault.

     options : n_txq_desc: optional string, containing an integer, in range 1 to
     4,096
	    Specifies the tx queue size (number tx descriptors) for dpdk  ports.
	    The  value must be a power of 2, less than 4096 and supported by the
	    hardware of the device being configured. If not specified or an  in-
	    correct  value is specified, 2048 tx descriptors will be used by de-
	    fault.

     options : dpdk-vf-mac: optional string
	    Ethernet address to set for this VF interface. If unset then the de-
	    fault MAC address is used:

	    *	   For most drivers, the default MAC address assigned  by  their
		   hardware.

	    *	   For	bifurcated drivers, the MAC currently used by the kernel
		   netdevice.

	    This option may only be used with dpdk VF representors.

     other_config : tx-steering: optional string, either hash or thread
	    Specifies the Tx steering mode for the interface.

	    thread enables static (1:1) thread-to-txq mapping when the number of
	    Tx queues is greater than number of PMD threads, and  dynamic  (N:1)
	    mapping  if equal or lower. In this mode a single thread can not use
	    more than 1 transmit queue of a given port.

	    hash enables hash-based Tx steering, which distributes  the  packets
	    on all the transmit queues based on their 5-tuples hashes.

	    Defaults to thread.

   EMC (Exact Match Cache) Configuration:

     These settings controls behaviour of EMC lookups/insertions for packets re-
     ceived from the interface.

     other_config : emc-enable: optional string, either true or false
	    Specifies if Exact Match Cache (EMC) should be used while processing
	    packets  received from this interface. If true, other_config:emc-in-
	    sert-inv-prob will have effect on this interface.

	    Defaults to true.

   MTU:

     The MTU (maximum transmission unit) is the largest amount of data that  can
     fit  into a single Ethernet frame. The standard Ethernet MTU is 1500 bytes.
     Some physical media and many kinds of virtual interfaces can be  configured
     with higher MTUs.

     A	client	may  change  an  interface  MTU  by filling in mtu_request. Open
     vSwitch then reports in mtu the currently configured value.

     mtu: optional integer
	    The currently configured MTU for the interface.

	    This column will be empty for an interface that does not have an MTU
	    as, for example, some kinds of tunnels do not.

	    Open vSwitch sets this column's value, so other clients should treat
	    it as read-only.

     mtu_request: optional integer, at least 1
	    Requested MTU (Maximum  Transmission  Unit)  for  the  interface.  A
	    client can fill this column to change the MTU of an interface.

	    RFC 791 requires every internet module to be able to forward a data-
	    gram of 68 octets without further fragmentation. The maximum size of
	    an IP packet is 65535 bytes.

	    If	this  is  not  set  and if the interface has internal type, Open
	    vSwitch will change the MTU to match the minimum of the other inter-
	    faces in the bridge.

   Interface Status:

     Status information about interfaces attached to bridges,  updated	every  5
     seconds.  Not  all  interfaces have all of these properties; virtual inter-
     faces don't have a link speed, for  example.  Non-applicable  columns  will
     have empty values.

     admin_state: optional string, either down or up
	    The administrative state of the physical network link.

     link_state: optional string, either down or up
	    The  observed state of the physical network link. This is ordinarily
	    the link's carrier status. If the interface's Port is a bond config-
	    ured for miimon monitoring, it is instead the network link's  miimon
	    status.

     link_resets: optional integer
	    The number of times Open vSwitch has observed the link_state of this
	    Interface change.

     link_speed: optional integer
	    The  negotiated speed of the physical network link. Valid values are
	    positive integers greater than 0.

     duplex: optional string, either full or half
	    The duplex mode of the physical network link.

     lacp_current: optional boolean
	    Boolean value indicating LACP status for this  interface.  If  true,
	    this  interface has current LACP information about its LACP partner.
	    This information may be used to monitor the health of interfaces  in
	    a  LACP  enabled  port. This column will be empty if LACP is not en-
	    abled.

     status: map of string-string pairs
	    Key-value pairs that report port status. Supported status values are
	    type-dependent; some interfaces may not  have  a  valid  status:dri-
	    ver_name, for example.

     status : driver_name: optional string
	    The name of the device driver controlling the network adapter.

     status : driver_version: optional string
	    The  version  string  of  the  device driver controlling the network
	    adapter.

     status : firmware_version: optional string
	    The version string of the network adapter's firmware, if available.

     status : source_ip: optional string
	    The source IP address used for an IPv4/IPv6 tunnel	end-point,  such
	    as gre.

     status : tunnel_egress_iface: optional string
	    Egress interface for tunnels. Currently only relevant for tunnels on
	    Linux systems, this column will show the name of the interface which
	    is	responsible  for routing traffic destined for the configured op-
	    tions:remote_ip. This could be  an	internal  interface  such  as  a
	    bridge port.

     status : tunnel_egress_iface_carrier: optional string, either down or up
	    Whether carrier is detected on status:tunnel_egress_iface.

   dpdk:

     DPDK specific interface status options.

     status : port_no: optional string
	    DPDK port ID.

     status : numa_id: optional string
	    NUMA socket ID to which an Ethernet device is connected.

     status : min_rx_bufsize: optional string
	    Minimum size of RX buffer.

     status : max_rx_pktlen: optional string
	    Maximum configurable length of RX pkt.

     status : max_rx_queues: optional string
	    Maximum number of RX queues.

     status : max_tx_queues: optional string
	    Maximum number of TX queues.

     status : max_mac_addrs: optional string
	    Maximum number of MAC addresses.

     status : max_hash_mac_addrs: optional string
	    Maximum number of hash MAC addresses for MTA and UTA.

     status : max_vfs: optional string
	    Maximum number of hash MAC addresses for MTA and UTA. Maximum number
	    of VFs.

     status : max_vmdq_pools: optional string
	    Maximum number of VMDq pools.

     status : if_type: optional string
	    Interface type ID according to IANA ifTYPE MIB definitions.

     status : if_descr: optional string
	    Interface description string.

     status : pci-vendor_id: optional string
	    Vendor ID of PCI device.

     status : pci-device_id: optional string
	    Device ID of PCI device.

     status : dpdk-vf-mac: optional string
	    Ethernet  address  set for this VF interface. Only reported for dpdk
	    VF representors.

   dpdkvhostuser:

     dpdkvhostuser and dpdkvhostuserclient netdev specific interface status  in-
     formation.

     status : mode: optional string
	    client  (connecting)  or server (listening) in the socket communica-
	    tion.

     status : features: optional string
	    virtio features bitmap as per virtio specification.

     status : num_of_vrings: optional string
	    The number of available virtqueues.

     status : numa: optional string
	    The numa id of the device and guest memory.

     status : socket: optional string
	    The path to the socket used for communication.

     status : status: optional string
	    Status of connection to the device.

     status : vring_n_size: optional string
	    Each virtqueue  will  have	it's  size  reported,  where  n  is  the
	    virtqueue number from 0..(num_of_vrings-1).

     status : userspace-tso: optional string
	    Whether userspace-tso is enabled or disabled.

   Statistics:

     Key-value	pairs  that report interface statistics. The current implementa-
     tion updates these counters periodically. The update period  is  controlled
     by other_config:stats-update-interval in the Open_vSwitch table. Future im-
     plementations  may  update them when an interface is created, when they are
     queried (e.g. using an OVSDB select operation), and just before  an  inter-
     face  is  deleted	due  to virtual interface hot-unplug or VM shutdown, and
     perhaps at other times, but not on any regular periodic basis.

     These  are  the  same  statistics	reported  by  OpenFlow	in  its   struct
     ofp_port_stats  structure. If an interface does not support a given statis-
     tic, then that pair is omitted.

   Statistics: Successful transmit and receive counters:

     statistics : rx_packets: optional integer
	    Number of received packets.

     statistics : rx_bytes: optional integer
	    Number of received bytes.

     statistics : tx_packets: optional integer
	    Number of transmitted packets.

     statistics : tx_bytes: optional integer
	    Number of transmitted bytes.

   Statistics: Receive errors:

     statistics : rx_dropped: optional integer
	    Number of packets dropped by RX.

     statistics : rx_frame_err: optional integer
	    Number of frame alignment errors.

     statistics : rx_over_err: optional integer
	    Number of packets with RX overrun.

     statistics : rx_crc_err: optional integer
	    Number of CRC errors.

     statistics : rx_errors: optional integer
	    Total number of receive errors, greater than or equal to the sum  of
	    the above.

   Statistics: Transmit errors:

     statistics : tx_dropped: optional integer
	    Number of packets dropped by TX.

     statistics : collisions: optional integer
	    Number of collisions.

     statistics : tx_errors: optional integer
	    Total number of transmit errors, greater than or equal to the sum of
	    the above.

   Ingress Policing:

     These settings control ingress policing for packets received on this inter-
     face. On a physical interface, this limits the rate at which traffic is al-
     lowed  into  the  system from the outside; on a virtual interface (one con-
     nected to a virtual machine), this limits the rate at which the VM is  able
     to transmit.

     Policing  is  a simple form of quality-of-service that simply drops packets
     received in excess of the configured rate. Due to its simplicity,	policing
     is  usually less accurate and less effective than egress QoS (which is con-
     figured using the QoS and Queue tables).

     Policing settings can be set with byte rate or packet rate, and they can be
     configured together, in which case they take effect  together,  that  means
     the smaller speed limit of them is in effect.

     Currently,  byte  rate  policing is implemented on Linux and OVS with DPDK,
     while packet rate policing is only implemented on Linux. Both Linux and OVS
     DPDK implementations use a simple ``token bucket'' approach.

     Byte rate policing:

	    *	   The size of the bucket corresponds to ingress_policing_burst.
		   Initially the bucket is full.

	    *	   Whenever a packet is received, its size (converted to tokens)
		   is compared to the number of tokens currently in the  bucket.
		   If  the required number of tokens are available, they are re-
		   moved and the packet is forwarded. Otherwise, the  packet  is
		   dropped.

	    *	   Whenever  it  is not full, the bucket is refilled with tokens
		   at the rate specified by ingress_policing_rate.

     Packet rate policing:

	    *	   The size of the bucket  corresponds	to  ingress_policing_kp-
		   kts_burst. Initially the bucket is full.

	    *	   Whenever a packet is received, it will consume one token from
		   the	current bucket. If the token is available in the bucket,
		   it's removed and the  packet  is  forwarded.  Otherwise,  the
		   packet is dropped.

	    *	   Whenever  it  is not full, the bucket is refilled with tokens
		   at the rate specified by ingress_policing_kpkts_rate.

     Policing interacts badly with some network protocols, and	especially  with
     fragmented  IP  packets.  Suppose	that there is enough network activity to
     keep the bucket nearly empty all the time. Then this token bucket algorithm
     will forward a single packet every so often, with the period  depending  on
     packet size and on the configured rate. All of the fragments of an IP pack-
     ets are normally transmitted back-to-back, as a group. In such a situation,
     therefore,  only one of these fragments will be forwarded and the rest will
     be dropped. IP does not provide any way for the intended recipient  to  ask
     for  only the remaining fragments. In such a case there are two likely pos-
     sibilities for what will happen next: either  all	of  the  fragments  will
     eventually  be retransmitted (as TCP will do), in which case the same prob-
     lem will recur, or the sender will not realize that  its  packet  has  been
     dropped and data will simply be lost (as some UDP-based protocols will do).
     Either way, it is possible that no forward progress will ever occur.

     ingress_policing_rate: integer, at least 0
	    Maximum  rate for data received on this interface, in kbps. Data re-
	    ceived faster than this rate is dropped. Set to 0 (the  default)  to
	    disable policing.

     ingress_policing_kpkts_rate: integer, at least 0
	    Maximum rate for data received on this interface, in kpps (1 kpps is
	    1000  pps). Data received faster than this rate is dropped. Set to 0
	    (the default) to disable policing.

     ingress_policing_burst: integer, at least 0
	    Maximum burst size for data received on this interface, in	kb.  The
	    default  burst  size if set to 0 is 8000 kbit. This value has no ef-
	    fect if ingress_policing_rate is 0.

	    Specifying a larger burst size lets the algorithm be more forgiving,
	    which is important for protocols like TCP  that  react  severely  to
	    dropped  packets.  The burst size should be at least the size of the
	    interface's MTU. Specifying a value that is numerically at least  as
	    large  as  80%  of	ingress_policing_rate  helps  TCP come closer to
	    achieving the full rate.

     ingress_policing_kpkts_burst: integer, at least 0
	    Maximum burst size for data received on this interface, in kpkts  (1
	    kpkts is 1000 packets). The default burst size if set to 0 is 16 kp-
	    kts. This value has no effect if ingress_policing_kpkts_rate is 0.

	    Specifying a larger burst size lets the algorithm be more forgiving,
	    which  is  important  for  protocols like TCP that react severely to
	    dropped packets. Specifying a value that is numerically at least  as
	    large as 80% of ingress_policing_kpkts_rate helps TCP come closer to
	    achieving the full rate.

   Bidirectional Forwarding Detection (BFD):

     BFD,  defined  in RFC 5880 and RFC 5881, allows point-to-point detection of
     connectivity failures by occasional transmission of BFD  control  messages.
     Open  vSwitch  implements BFD to serve as a more popular and standards com-
     pliant alternative to CFM.

     BFD operates by regularly transmitting BFD control messages at a rate nego-
     tiated independently in each direction. Each endpoint specifies the rate at
     which it expects to receive control messages, and the rate at which  it  is
     willing  to transmit them. By default, Open vSwitch uses a detection multi-
     plier of three, meaning that an endpoint signals a  connectivity  fault  if
     three  consecutive  BFD  control  messages fail to arrive. In the case of a
     unidirectional connectivity issue, the system  not  receiving  BFD  control
     messages signals the problem to its peer in the messages it transmits.

     The  Open	vSwitch implementation of BFD aims to comply faithfully with RFC
     5880 requirements. Open vSwitch does not implement the optional Authentica-
     tion or ``Echo Mode'' features.

     OVS 2.13 and earlier intercepted and processed all BFD  packets.  OVS  2.14
     and  later  only intercept and process BFD packets destined to a configured
     BFD instance, and other BFD packets are made available to the OVS flow  ta-
     ble for forwarding.

   BFD Configuration:

     A	controller  sets up key-value pairs in the bfd column to enable and con-
     figure BFD.

     bfd : enable: optional string, either true or false
	    True to enable BFD on this Interface. If not specified, BFD will not
	    be enabled by default.

     bfd : min_rx: optional string, containing an integer, at least 1
	    The shortest interval, in milliseconds, at which  this  BFD  session
	    offers  to	receive  BFD  control  messages. The remote endpoint may
	    choose to send messages at a slower rate. Defaults to 1000.

     bfd : min_tx: optional string, containing an integer, at least 1
	    The shortest interval, in milliseconds, at which this BFD session is
	    willing to transmit BFD control messages. Messages will actually  be
	    transmitted  at  a slower rate if the remote endpoint is not willing
	    to receive as quickly as specified. Defaults to 100.

     bfd : decay_min_rx: optional string, containing an integer
	    An alternate receive interval, in milliseconds, that must be greater
	    than or  equal  to	bfd:min_rx.  The  implementation  switches  from
	    bfd:min_rx	to  bfd:decay_min_rx  when  there is no obvious incoming
	    data traffic at the interface, to reduce the CPU and bandwidth  cost
	    of	monitoring  an	idle  interface. This feature may be disabled by
	    setting a value  of  0.  This  feature  is	reset  whenever  bfd:de-
	    cay_min_rx or bfd:min_rx changes.

     bfd : forwarding_if_rx: optional string, either true or false
	    When true, traffic received on the Interface is used to indicate the
	    capability	of packet I/O. BFD control packets are still transmitted
	    and received. At least one BFD control packet must be received every
	    100 * bfd:min_rx amount of time. Otherwise, even if traffic are  re-
	    ceived, the bfd:forwarding will be false.

     bfd : cpath_down: optional string, either true or false
	    Set to true to notify the remote endpoint that traffic should not be
	    forwarded  to  this  system for some reason other than a connectivty
	    failure on the interface being  monitored.	The  typical  underlying
	    reason is ``concatenated path down,'' that is, that connectivity be-
	    yond the local system is down. Defaults to false.

     bfd : check_tnl_key: optional string, either true or false
	    Set  to  true to make BFD accept only control messages with a tunnel
	    key of zero. By default, BFD accepts control messages with any  tun-
	    nel key.

     bfd : bfd_local_src_mac: optional string
	    Set  to an Ethernet address in the form xx:xx:xx:xx:xx:xx to set the
	    MAC used as source for transmitted BFD packets. The default  is  the
	    mac address of the BFD enabled interface.

     bfd : bfd_local_dst_mac: optional string
	    Set  to an Ethernet address in the form xx:xx:xx:xx:xx:xx to set the
	    MAC used as destination for transmitted BFD packets. The default  is
	    00:23:20:00:00:01.

     bfd : bfd_remote_dst_mac: optional string
	    Set  to an Ethernet address in the form xx:xx:xx:xx:xx:xx to set the
	    MAC used for checking the destination of received BFD packets. Pack-
	    ets with different destination MAC will not  be  considered  as  BFD
	    packets.  If  not  specified the destination MAC address of received
	    BFD packets are not checked.

     bfd : bfd_src_ip: optional string
	    Set to an IPv4 address to set the IP  address  used  as  source  for
	    transmitted BFD packets. The default is 169.254.1.1.

     bfd : bfd_dst_ip: optional string
	    Set to an IPv4 address to set the IP address used as destination for
	    transmitted BFD packets. The default is 169.254.1.0.

     bfd : oam: optional string
	    Some  tunnel  protocols (such as Geneve) include a bit in the header
	    to indicate that the encapsulated packet is an OAM frame. By setting
	    this to true, BFD packets will be marked as OAM if	encapsulated  in
	    one of these tunnels.

     bfd : mult: optional string, containing an integer, in range 1 to 255
	    The  BFD detection multiplier, which defaults to 3. An endpoint sig-
	    nals a connectivity fault if the given  number  of	consecutive  BFD
	    control messages fail to arrive.

   BFD Status:

     The switch sets key-value pairs in the bfd_status column to report the sta-
     tus of BFD on this interface. When BFD is not enabled, with bfd:enable, the
     switch clears all key-value pairs from bfd_status.

     bfd_status : state: optional string, one of admin_down, down, init, or up
	    Reports  the  state  of  the  BFD  session. The BFD session is fully
	    healthy and negotiated if UP.

     bfd_status : forwarding: optional string, either true or false
	    Reports whether the BFD session believes this Interface may be  used
	    to	forward  traffic. Typically this means the local session is sig-
	    naling UP, and the remote system isn't signaling a problem	such  as
	    concatenated path down.

     bfd_status : diagnostic: optional string
	    A  diagnostic code specifying the local system's reason for the last
	    change in session state. The error messages are defined  in  section
	    4.1 of [RFC 5880].

     bfd_status : remote_state: optional string, one of admin_down, down, init,
     or up
	    Reports the state of the remote endpoint's BFD session.

     bfd_status : remote_diagnostic: optional string
	    A diagnostic code specifying the remote system's reason for the last
	    change  in	session state. The error messages are defined in section
	    4.1 of [RFC 5880].

     bfd_status : flap_count: optional string, containing an integer, at least 0
	    Counts the number of bfd_status:forwarding flaps since start. A flap
	    is considered as a change of the bfd_status:forwarding value.

   Connectivity Fault Management:

     802.1ag Connectivity Fault Management (CFM) allows a group  of  Maintenance
     Points  (MPs)  called a Maintenance Association (MA) to detect connectivity
     problems with each other. MPs within a MA should have complete  and  exclu-
     sive  interconnectivity. This is verified by occasionally broadcasting Con-
     tinuity Check Messages (CCMs) at a configurable transmission interval.

     According to the 802.1ag specification, each Maintenance  Point  should  be
     configured  out-of-band  with a list of Remote Maintenance Points it should
     have connectivity to. Open vSwitch differs from the specification	in  this
     area. It simply assumes the link is faulted if no Remote Maintenance Points
     are reachable, and considers it not faulted otherwise.

     When operating over tunnels which have no in_key, or an in_key of flow. CFM
     will only accept CCMs with a tunnel key of zero.

     cfm_mpid: optional integer
	    A  Maintenance  Point  ID  (MPID)  uniquely identifies each endpoint
	    within a Maintenance Association. The MPID is used to identify  this
	    endpoint  to  other Maintenance Points in the MA. Each end of a link
	    being monitored should have a different MPID. Must be configured  to
	    enable CFM on this Interface.

	    According to the 802.1ag specification, MPIDs can only range between
	    [1,  8191].  However,  extended mode (see other_config:cfm_extended)
	    supports eight byte MPIDs.

     cfm_flap_count: optional integer
	    Counts the number of cfm fault flapps since boot. A flap is  consid-
	    ered to be a change of the cfm_fault value.

     cfm_fault: optional boolean
	    Indicates  a connectivity fault triggered by an inability to receive
	    heartbeats from any remote endpoint. When a fault  is  triggered  on
	    Interfaces participating in bonds, they will be disabled.

	    Faults  can  be triggered for several reasons. Most importantly they
	    are triggered when no CCMs are received for a period  of  3.5  times
	    the  transmission  interval. Faults are also triggered when any CCMs
	    indicate that a Remote Maintenance Point is not receiving  CCMs  but
	    able  to  send  them.  Finally, a fault is triggered if a CCM is re-
	    ceived which indicates unexpected configuration. Notably, this  case
	    arises when a CCM is received which advertises the local MPID.

     cfm_fault_status : recv: none
	    Indicates  a  CFM fault was triggered due to a lack of CCMs received
	    on the Interface.

     cfm_fault_status : rdi: none
	    Indicates a CFM fault was triggered due to the reception  of  a  CCM
	    with  the  RDI  bit flagged. Endpoints set the RDI bit in their CCMs
	    when they are not receiving CCMs themselves.  This	typically  indi-
	    cates a unidirectional connectivity failure.

     cfm_fault_status : maid: none
	    Indicates  a  CFM  fault was triggered due to the reception of a CCM
	    with a MAID other than the one Open vSwitch uses. CFM broadcasts are
	    tagged with an identification number in addition to the MPID  called
	    the MAID. Open vSwitch only supports receiving CCM broadcasts tagged
	    with the MAID it uses internally.

     cfm_fault_status : loopback: none
	    Indicates  a  CFM  fault was triggered due to the reception of a CCM
	    advertising the same MPID configured in the cfm_mpid column of  this
	    Interface. This may indicate a loop in the network.

     cfm_fault_status : overflow: none
	    Indicates  a CFM fault was triggered because the CFM module received
	    CCMs from more remote endpoints than it can keep track of.

     cfm_fault_status : override: none
	    Indicates a CFM fault was manually triggered by an administrator us-
	    ing an ovs-appctl command.

     cfm_fault_status : interval: none
	    Indicates a CFM fault was triggered due to the reception  of  a  CCM
	    frame having an invalid interval.

     cfm_remote_opstate: optional string, either down or up
	    When in extended mode, indicates the operational state of the remote
	    endpoint as either up or down. See other_config:cfm_opstate.

     cfm_health: optional integer, in range 0 to 100
	    Indicates  the health of the interface as a percentage of CCM frames
	    received over 21 other_config:cfm_intervals. The health of an inter-
	    face is undefined if it is communicating with more than one  cfm_re-
	    mote_mpids. It reduces if healthy heartbeats are not received at the
	    expected  rate, and gradually improves as healthy heartbeats are re-
	    ceived at the desired rate. Every 21 other_config:cfm_intervals, the
	    health of the interface is refreshed.

	    As mentioned above, the faults can be triggered for several reasons.
	    The link health will deteriorate even if heartbeats are received but
	    they are reported to be unhealthy. An unhealthy  heartbeat	in  this
	    context  is a heartbeat for which either some fault is set or is out
	    of sequence. The interface health  can  be	100  only  on  receiving
	    healthy heartbeats at the desired rate.

     cfm_remote_mpids: set of integers
	    When  CFM is properly configured, Open vSwitch will occasionally re-
	    ceive CCM broadcasts. These broadcasts contain the MPID of the send-
	    ing Maintenance Point. The list of MPIDs from which  this  Interface
	    is	receiving  broadcasts from is regularly collected and written to
	    this column.

     other_config : cfm_interval: optional string, containing an integer
	    The interval, in milliseconds, between transmissions of  CFM  heart-
	    beats.  Three  missed  heartbeat  receptions indicate a connectivity
	    fault.

	    In standard operation only intervals of 3, 10, 100,  1,000,  10,000,
	    60,000,  or  600,000  ms are supported. Other values will be rounded
	    down to the nearest value on the list. Extended mode (see other_con-
	    fig:cfm_extended) supports any interval up to 65,535 ms.  In  either
	    mode, the default is 1000 ms.

	    We do not recommend using intervals less than 100 ms.

     other_config : cfm_extended: optional string, either true or false
	    When  true, the CFM module operates in extended mode. This causes it
	    to use a nonstandard destination address to avoid  conflicting  with
	    compliant  implementations	which may be running concurrently on the
	    network. Furthermore, extended mode increases the  accuracy  of  the
	    cfm_interval  configuration parameter by breaking wire compatibility
	    with 802.1ag compliant implementations.  And  extended  mode  allows
	    eight byte MPIDs. Defaults to false.

     other_config : cfm_demand: optional string, either true or false
	    When true, and other_config:cfm_extended is true, the CFM module op-
	    erates  in demand mode. When in demand mode, traffic received on the
	    Interface is used to indicate liveness. CCMs are  still  transmitted
	    and  received.  At	least  one  CCM  must  be  received  every 100 *
	    other_config:cfm_interval amount of time. Otherwise, even if traffic
	    are received, the CFM module will raise the connectivity fault.

	    Demand mode has a couple of caveats:

	    *	   To ensure that ovs-vswitchd has enough time to  pull  statis-
		   tics  from  the datapath, the fault detection interval is set
		   to 3.5 * MAX(other_config:cfm_interval, 500) ms.

	    *	   To avoid ambiguity, demand mode disables  itself  when  there
		   are multiple remote maintenance points.

	    *	   If  the  Interface  is heavily congested, CCMs containing the
		   other_config:cfm_opstate  status  may  be   dropped	 causing
		   changes in the operational state to be delayed. Similarly, if
		   CCMs  containing the RDI bit are not received, unidirectional
		   link failures may not be detected.

     other_config : cfm_opstate: optional string, either down or up
	    When down, the CFM module marks all  CCMs  it  generates  as  opera-
	    tionally down without triggering a fault. This allows remote mainte-
	    nance  points  to  choose not to forward traffic to the Interface on
	    which this CFM module is running. Currently, in  Open  vSwitch,  the
	    opdown  bit  of  CCMs affects Interfaces participating in bonds, and
	    the bundle OpenFlow action. This setting is ignored when CFM is  not
	    in extended mode. Defaults to up.

     other_config : cfm_ccm_vlan: optional string, containing an integer, in
     range 1 to 4,095
	    When set, the CFM module will apply a VLAN tag to all CCMs it gener-
	    ates  with	the  given value. May be the string random in which case
	    each CCM will be tagged with a different randomly generated VLAN.

     other_config : cfm_ccm_pcp: optional string, containing an integer, in
     range 1 to 7
	    When set, the CFM module will apply a VLAN tag to all CCMs it gener-
	    ates with the given PCP value, the VLAN ID of the tag is governed by
	    the value of other_config:cfm_ccm_vlan. If other_config:cfm_ccm_vlan
	    is unset, a VLAN ID of zero is used.

   Bonding Configuration:

     other_config : lacp-port-id: optional string, containing an integer, in
     range 1 to 65,535
	    The LACP port ID of this Interface. Port IDs are used in LACP  nego-
	    tiations to identify individual ports participating in a bond.

     other_config : lacp-port-priority: optional string, containing an integer,
     in range 1 to 65,535
	    The  LACP  port priority of this Interface. In LACP negotiations In-
	    terfaces with numerically lower priorities are preferred for  aggre-
	    gation.

     other_config : lacp-aggregation-key: optional string, containing an inte-
     ger, in range 1 to 65,535
	    The  LACP aggregation key of this Interface. Interfaces with differ-
	    ent aggregation keys may not be active within a given  Port  at  the
	    same time.

   Virtual Machine Identifiers:

     These  key-value pairs specifically apply to an interface that represents a
     virtual Ethernet interface connected to a virtual machine. These  key-value
     pairs should not be present for other types of interfaces. Keys whose names
     end in -uuid have values that uniquely identify the entity in question. For
     a	Citrix	XenServer hypervisor, these values are UUIDs in RFC 4122 format.
     Other hypervisors may use other formats.

     external_ids : attached-mac: optional string
	    The MAC address programmed into the ``virtual  hardware''  for  this
	    interface, in the form xx:xx:xx:xx:xx:xx. For Citrix XenServer, this
	    is the value of the MAC field in the VIF record for this interface.

     external_ids : iface-id: optional string
	    A  system-unique  identifier  for  the interface. On XenServer, this
	    will commonly be the same as external_ids:xs-vif-uuid.

     external_ids : iface-status: optional string, either active or inactive
	    Hypervisors may sometimes have more than  one  interface  associated
	    with a given external_ids:iface-id, only one of which is actually in
	    use  at  a	given time. For example, in some circumstances XenServer
	    has both a ``tap'' and a  ``vif''  interface  for  a  single  exter-
	    nal_ids:iface-id,  but only uses one of them at a time. A hypervisor
	    that behaves this way must mark the currently in use  interface  ac-
	    tive  and the others inactive. A hypervisor that never has more than
	    one interface for a given external_ids:iface-id may mark that inter-
	    face active or omit external_ids:iface-status entirely.

	    During VM migration, a given external_ids:iface-id might transiently
	    be marked active on two different hypervisors. That is, active means
	    that this external_ids:iface-id is the active instance within a sin-
	    gle hypervisor, not in a broader scope. There is one exception: some
	    hypervisors support ``migration'' from a given hypervisor to  itself
	    (most often for test purposes). During such a ``migration,'' two in-
	    stances  of  a  single  external_ids:iface-id  might both be briefly
	    marked active on a single hypervisor.

     external_ids : xs-vif-uuid: optional string
	    The virtual interface associated with this interface.

     external_ids : xs-network-uuid: optional string
	    The virtual network to which this interface is attached.

     external_ids : vm-id: optional string
	    The VM to which this interface belongs. On XenServer, this	will  be
	    the same as external_ids:xs-vm-uuid.

     external_ids : xs-vm-uuid: optional string
	    The VM to which this interface belongs.

   Auto Attach Configuration:

     Auto Attach configuration for a particular interface.

     lldp : enable: optional string, either true or false
	    True  to  enable LLDP on this Interface. If not specified, LLDP will
	    be disabled by default.

   Flow control Configuration:

     Ethernet flow control defined in IEEE 802.1Qbb  provides  link  level  flow
     control  using  MAC pause frames. Implemented only for interfaces with type
     dpdk.

     options : rx-flow-ctrl: optional string, either true or false
	    Set to true to enable Rx flow control on physical ports. By default,
	    Rx flow control is disabled.

     options : tx-flow-ctrl: optional string, either true or false
	    Set to true to enable Tx flow control on physical ports. By default,
	    Tx flow control is disabled.

     options : flow-ctrl-autoneg: optional string, either true or false
	    Set to true to enable flow	control  auto  negotiation  on	physical
	    ports. By default, auto-neg is disabled.

   Link State Change detection mode:

     options : dpdk-lsc-interrupt: optional string, either true or false
	    Set  this  value  to true to configure interrupt mode for Link State
	    Change (LSC) detection instead of poll mode for the DPDK interface.

	    If this value is not set, poll mode is configured.

	    This parameter has an effect only on netdev dpdk interfaces.

   Common Columns:

     The overall purpose of these columns is described under Common  Columns  at
     the beginning of this document.

     other_config: map of string-string pairs

     external_ids: map of string-string pairs

Flow_Table TABLE
     Configuration for a particular OpenFlow table.

   Summary:
     name			   optional string
     Eviction Policy:
       flow_limit		   optional integer, at least 0
       overflow_policy		   optional string, either evict or refuse
       groups			   set of strings
     Classifier Optimization:
       prefixes 		   set of up to 3 strings
     Common Columns:
       external_ids		   map of string-string pairs

   Details:
     name: optional string
	    The  table's  name.  Set  this  column  to change the name that con-
	    trollers will receive  when  they  request	table  statistics,  e.g.
	    ovs-ofctl dump-tables. The name does not affect switch behavior.

   Eviction Policy:

     Open vSwitch supports limiting the number of flows that may be installed in
     a	flow  table,  via the flow_limit column. When adding a flow would exceed
     this limit, by default Open vSwitch reports an error,  but  there	are  two
     ways to configure Open vSwitch to instead delete (``evict'') a flow to make
     room for the new one:

	    *	   Set the overflow_policy column to evict.

	    *	   Send  an  OpenFlow 1.4+ ``table mod request'' to enable evic-
		   tion for the flow table (e.g. ovs-ofctl -O OpenFlow14 mod-ta-
		   ble br0 0 evict to enable eviction on flow table 0 of  bridge
		   br0).

     When  a  flow  must be evicted due to overflow, the flow to evict is chosen
     through an approximation of the following algorithm. This algorithm is used
     regardless of how eviction was enabled:

	    1.	Divide the flows in the table into groups based on the values of
		the fields or subfields specified in the groups column, so  that
		all of the flows in a given group have the same values for those
		fields.  If  a flow does not specify a given field, that field's
		value is treated as 0. If groups is empty, then all of the flows
		in the flow table are treated as a single group.

	    2.	Consider the flows in the largest group, that is, the group that
		contains the greatest number of flows. If two or more groups all
		have the same largest number of flows, consider the flows in all
		of those groups.

	    3.	If the flows under consideration have different importance  val-
		ues,  eliminate  from  consideration any flows except those with
		the lowest importance. (``Importance,'' a 16-bit  integer  value
		attached to each flow, was introduced in OpenFlow 1.4. Flows in-
		serted with older versions of OpenFlow always have an importance
		of 0.)

	    4.	Among  the  flows  under consideration, choose the flow that ex-
		pires soonest for eviction.

     The eviction process only considers flows that have an idle  timeout  or  a
     hard  timeout.  That is, eviction never deletes permanent flows. (Permanent
     flows do count against flow_limit.)

     flow_limit: optional integer, at least 0
	    If set, limits the number of flows that may be added to  the  table.
	    Open vSwitch may limit the number of flows in a table for other rea-
	    sons,  e.g. due to hardware limitations or for resource availability
	    or performance reasons.

     overflow_policy: optional string, either evict or refuse
	    Controls the switch's behavior when an OpenFlow flow table modifica-
	    tion request would add flows in excess of flow_limit. The  supported
	    values are:

	    refuse
		   Refuse  to  add  the  flow or flows. This is also the default
		   policy when overflow_policy is unset.

	    evict  Delete a flow chosen according  to  the  algorithm  described
		   above.

     groups: set of strings
	    When  overflow_policy  is  evict, this controls how flows are chosen
	    for eviction when the flow table would otherwise  exceed  flow_limit
	    flows. Its value is a set of NXM fields or sub-fields, each of which
	    takes   one   of   the  forms  field[]  or	field[start..end],  e.g.
	    NXM_OF_IN_PORT[]. Please see meta-flow.h for a complete list of  NXM
	    field names.

	    Open vSwitch ignores any invalid or unknown field specifications.

	    When  eviction  is	not  enabled, via overflow_policy or an OpenFlow
	    1.4+ ``table mod,'' this column has no effect.

   Classifier Optimization:

     prefixes: set of up to 3 strings
	    This string set specifies which fields should be  used  for  address
	    prefix tracking. Prefix tracking allows the classifier to skip rules
	    with longer than necessary prefixes, resulting in better wildcarding
	    for datapath flows.

	    Prefix tracking may be beneficial when a flow table contains matches
	    on	IP  address  fields  with different prefix lengths. For example,
	    when a flow table contains IP address matches on both full addresses
	    and proper prefixes, the full address matches will	typically  cause
	    the  datapath flow to un-wildcard the whole address field (depending
	    on flow entry priorities). In this case each packet with a different
	    address gets handed to the userspace for flow processing and  gener-
	    ates its own datapath flow. With prefix tracking enabled for the ad-
	    dress field in question packets with addresses matching shorter pre-
	    fixes  would  generate  datapath  flows where the irrelevant address
	    bits are wildcarded, allowing the same datapath flow to  handle  all
	    the  packets  within the prefix in question. In this case many user-
	    space upcalls can be avoided and the overall performance can be bet-
	    ter.

	    This is a performance optimization only, so packets will receive the
	    same treatment with or without prefix tracking.

	    The supported fields are: tun_id,  tun_src,  tun_dst,  tun_ipv6_src,
	    tun_ipv6_dst,   nw_src,  nw_dst  (or  aliases  ip_src  and	ip_dst),
	    ipv6_src, and ipv6_dst. (Using this feature for  tun_id  would  only
	    make sense if the tunnel IDs have prefix structure similar to IP ad-
	    dresses.)

	    By	default, the prefixes=ip_dst,ip_src are used on each flow table.
	    This instructs the flow classifier to track the IP	destination  and
	    source addresses used by the rules in this specific flow table.

	    The  keyword  none	is recognized as an explicit override of the de-
	    fault values, causing no prefix fields to be tracked.

	    To set the prefix fields, the flow table record needs to exist:

	    ovs-vsctl set Bridge br0 flow_tables:0=@N1 -- --id=@N1 create
	    Flow_Table name=table0
		   Creates a flow table record for the OpenFlow table number 0.

	    ovs-vsctl set Flow_Table table0 prefixes=ip_dst,ip_src
		   Enables prefix tracking for IP source and destination address
		   fields.

	    There is a maximum number of fields that can be enabled for any  one
	    flow table. Currently this limit is 3.

   Common Columns:

     The  overall  purpose of these columns is described under Common Columns at
     the beginning of this document.

     external_ids: map of string-string pairs

QoS TABLE
     Quality of Service (QoS) configuration for each Port that references it.

   Summary:
     type			   string
     queues			   map of integer-Queue pairs, key in range 0 to
				   4,294,967,295
     Configuration for linux-htb and linux-hfsc:
       other_config : max-rate	   optional string, containing an integer
     Configuration for egress-policer QoS:
       other_config : cir	   optional string, containing an integer
       other_config : cbs	   optional string, containing an integer
       other_config : eir	   optional string, containing an integer
       other_config : ebs	   optional string, containing an integer
     Configuration for linux-sfq:
       other_config : perturb	   optional string, containing an integer
       other_config : quantum	   optional string, containing an integer
     Configuration for linux-netem:
       other_config : latency	   optional string, containing an integer
       other_config : limit	   optional string, containing an integer
       other_config : loss	   optional string, containing an integer
     Common Columns:
       other_config		   map of string-string pairs
       external_ids		   map of string-string pairs

   Details:
     type: string
	    The type of QoS to implement. The currently defined types are listed
	    below:

	    linux-htb
		   Linux ``hierarchy token bucket''  classifier.  See  tc-htb(8)
		   (also  at http://linux.die.net/man/8/tc-htb) and the HTB man-
		   ual (http://luxik.cdi.cz/~devik/qos/htb/manual/userg.htm) for
		   information on how this classifier works and how to configure
		   it.

	    linux-hfsc
		   Linux  "Hierarchical  Fair  Service	Curve"	classifier.  See
		   http://linux-ip.net/articles/hfsc.en/  for information on how
		   this classifier works.

	    linux-sfq
		   Linux  ``Stochastic	Fairness  Queueing''   classifier.   See
		   tc-sfq(8) (also at http://linux.die.net/man/8/tc-sfq) for in-
		   formation on how this classifier works.

	    linux-codel
		   Linux  ``Controlled Delay'' classifier. See tc-codel(8) (also
		   at http://man7.org/linux/man-pages/man8/tc-codel.8.html)  for
		   information on how this classifier works.

	    linux-fq_codel
		   Linux  ``Fair Queuing with Controlled Delay'' classifier. See
		   tc-fq_codel(8)		     (also		      at
		   http://man7.org/linux/man-pages/man8/tc-fq_codel.8.html)  for
		   information on how this classifier works.

	    linux-netem
		   Linux ``Network Emulator'' classifier. See tc-netem(8)  (also
		   at  http://man7.org/linux/man-pages/man8/tc-netem.8.html) for
		   information on how this classifier works.

	    linux-noop
		   Linux ``No operation.''  By	default,  Open	vSwitch  manages
		   quality  of	service on all of its configured ports. This can
		   be helpful, but sometimes administrators prefer to use  other
		   software  to manage QoS. This type prevents Open vSwitch from
		   changing the QoS configuration for a port.

	    egress-policer
		   A DPDK egress policer algorithm using the DPDK rte_meter  li-
		   brary. The rte_meter library provides an implementation which
		   allows  the metering and policing of traffic. The implementa-
		   tion in OVS essentially creates a single token bucket used to
		   police traffic. It should be noted that when the rte_meter is
		   configured as part of QoS there will be a  performance  over-
		   head as the rte_meter itself will consume CPU cycles in order
		   to  police  traffic. These CPU cycles ordinarily are used for
		   packet proccessing. As such the drop in performance	will  be
		   noticed in terms of overall aggregate traffic throughput.

	    trtcm-policer
		   A  DPDK  egress  policer algorithm using RFC 4115's Two-Rate,
		   Three-Color marker. It's  a	two-level  hierarchical  policer
		   which  first does a color-blind marking of the traffic at the
		   queue level, followed by a color-aware marking  at  the  port
		   level.  At  the end traffic marked as Green or Yellow is for-
		   warded, Red is dropped. For details on how traffic is marked,
		   see RFC 4115. If the ``default queue'', 0, is not  configured
		   it's  automatically created with the same other_config values
		   as the physical port.

     queues: map of integer-Queue pairs, key in range 0 to 4,294,967,295
	    A map from queue numbers to Queue records. The  supported  range  of
	    queue  numbers depend on type. The queue numbers are the same as the
	    queue_id used in OpenFlow in  struct  ofp_action_enqueue  and  other
	    structures.

	    Queue  0 is the ``default queue.'' It is used by OpenFlow output ac-
	    tions when no specific queue has been set. When no configuration for
	    queue 0 is present, it is automatically configured	as  if	a  Queue
	    record  with empty dscp and other_config columns had been specified.
	    (Before version 1.6, Open vSwitch would leave queue  0  unconfigured
	    in	this case. With some queuing disciplines, this dropped all pack-
	    ets destined for the default queue.)

   Configuration for linux-htb and linux-hfsc:

     The linux-htb and linux-hfsc classes support the following key-value pair:

     other_config : max-rate: optional string, containing an integer
	    Maximum rate shared by all queued traffic, in  bit/s.  Optional.  If
	    not  specified,  for  physical  interfaces,  the default is the link
	    rate. For other interfaces or if the link rate cannot be determined,
	    the default is currently 100 Mbps.

   Configuration for egress-policer QoS:

     QoS type egress-policer provides egress policing for userspace  port  types
     with DPDK. It has the following key-value pairs defined.

     other_config : cir: optional string, containing an integer
	    The  Committed  Information  Rate  (CIR)  is measured in bytes of IP
	    packets per second, i.e. it includes the IP  header,  but  not  link
	    specific (e.g. Ethernet) headers. This represents the bytes per sec-
	    ond rate at which the token bucket will be updated. The cir value is
	    calculated	by (pps x packet data size). For example assuming a user
	    wishes to limit a stream consisting of 64 byte packets to 1  million
	    packets  per  second  the  CIR  would be set to to to 46000000. This
	    value can be broken into '1,000,000 x 46'. Where  1,000,000  is  the
	    policing rate for the number of packets per second and 46 represents
	    the  size  of  the	packet	data for a 64 bytes IP packet without 14
	    bytes Ethernet and 4 bytes FCS header.

     other_config : cbs: optional string, containing an integer
	    The Committed Burst Size (CBS) is measured in bytes and represents a
	    token bucket. At a minimum this value should be be set  to	the  ex-
	    pected largest size packet in the traffic stream. In practice larger
	    values  may  be  used to increase the size of the token bucket. If a
	    packet can be transmitted then the cbs will be  decremented  by  the
	    number of bytes/tokens of the packet. If there are not enough tokens
	    in the cbs bucket the packet will be dropped.

     other_config : eir: optional string, containing an integer
	    The Excess Information Rate (EIR) is measured in bytes of IP packets
	    per  second,  i.e.	it includes the IP header, but not link specific
	    (e.g. Ethernet) headers. This represents the bytes per  second  rate
	    at	which  the token bucket will be updated. The eir value is calcu-
	    lated by (pps x packet data  size).  For  example  assuming  a  user
	    wishes  to limit a stream consisting of 64 byte packets to 1 million
	    packets per second the EIR would be set  to  to  to  46000000.  This
	    value  can	be  broken into '1,000,000 x 46'. Where 1,000,000 is the
	    policing rate for the number of packets per second and 46 represents
	    the size of the packet data for a 64  bytes  IP  packet  without  14
	    bytes Ethernet and 4 bytes FCS header.

     other_config : ebs: optional string, containing an integer
	    The  Excess  Burst	Size (EBS) is measured in bytes and represents a
	    token bucket. At a minimum this value should be be set  to	the  ex-
	    pected largest size packet in the traffic stream. In practice larger
	    values  may  be  used to increase the size of the token bucket. If a
	    packet can be transmitted then the ebs will be  decremented  by  the
	    number of bytes/tokens of the packet. If there are not enough tokens
	    in the cbs bucket the packet might be dropped.

   Configuration for linux-sfq:

     The linux-sfq QoS supports the following key-value pairs:

     other_config : perturb: optional string, containing an integer
	    Number of seconds between consecutive perturbations in hashing algo-
	    rithm.  Different  flows  can end up in the same hash bucket causing
	    unfairness. Perturbation's goal is to  remove  possible  unfairness.
	    The default and recommended value is 10. Too low a value is discour-
	    aged because each perturbation can cause packet reordering.

     other_config : quantum: optional string, containing an integer
	    Number of bytes linux-sfq QoS can dequeue in one turn in round-robin
	    from  one flow. The default and recommended value is equal to inter-
	    face's MTU.

   Configuration for linux-netem:

     The linux-netem QoS supports the following key-value pairs:

     other_config : latency: optional string, containing an integer
	    Adds the chosen delay to the packets outgoing to chosen network  in-
	    terface. The latency value expressed in us.

     other_config : limit: optional string, containing an integer
	    Maximum  number  of packets the qdisc may hold queued at a time. The
	    default value is 1000.

     other_config : loss: optional string, containing an integer
	    Adds an independent loss probability to the  packets  outgoing  from
	    the chosen network interface.

   Common Columns:

     The  overall  purpose of these columns is described under Common Columns at
     the beginning of this document.

     other_config: map of string-string pairs

     external_ids: map of string-string pairs

Queue TABLE
     A configuration for a port output queue, used  in	configuring  Quality  of
     Service (QoS) features. May be referenced by queues column in QoS table.

   Summary:
     dscp			   optional integer, in range 0 to 63
     Configuration for linux-htb QoS:
       other_config : min-rate	   optional  string,  containing  an integer, at
				   least 1
       other_config : max-rate	   optional string, containing	an  integer,  at
				   least 1
       other_config : burst	   optional  string,  containing  an integer, at
				   least 1
       other_config : priority	   optional string, containing	an  integer,  in
				   range 0 to 4,294,967,295
     Configuration for linux-hfsc QoS:
       other_config : min-rate	   optional  string,  containing  an integer, at
				   least 1
       other_config : max-rate	   optional string, containing	an  integer,  at
				   least 1
     Common Columns:
       other_config		   map of string-string pairs
       external_ids		   map of string-string pairs

   Details:
     dscp: optional integer, in range 0 to 63
	    If set, Open vSwitch will mark all traffic egressing this Queue with
	    the  given	DSCP  bits.  Traffic egressing the default Queue is only
	    marked if it was explicitly selected as the Queue at  the  time  the
	    packet was output. If unset, the DSCP bits of traffic egressing this
	    Queue will remain unchanged.

   Configuration for linux-htb QoS:

     QoS  type linux-htb may use queue_ids less than 61440. It has the following
     key-value pairs defined.

     other_config : min-rate: optional string, containing an integer, at least 1
	    Minimum guaranteed bandwidth, in bit/s.

     other_config : max-rate: optional string, containing an integer, at least 1
	    Maximum allowed bandwidth, in bit/s.  Optional.  If  specified,  the
	    queue's rate will not be allowed to exceed the specified value, even
	    if	excess	bandwidth  is  available. If unspecified, defaults to no
	    limit.

     other_config : burst: optional string, containing an integer, at least 1
	    Burst size, in bits. This is the maximum amount of ``credits''  that
	    a  queue  can  accumulate while it is idle. Optional. Details of the
	    linux-htb implementation require a minimum burst  size,  so  a  too-
	    small burst will be silently ignored.

     other_config : priority: optional string, containing an integer, in range 0
     to 4,294,967,295
	    A  queue  with  a smaller priority will receive all the excess band-
	    width that it can use before a queue with a  larger  value	receives
	    any.  Specific priority values are unimportant; only relative order-
	    ing matters. Defaults to 0 if unspecified.

   Configuration for linux-hfsc QoS:

     QoS type linux-hfsc may use queue_ids less than 61440. It has the following
     key-value pairs defined.

     other_config : min-rate: optional string, containing an integer, at least 1
	    Minimum guaranteed bandwidth, in bit/s.

     other_config : max-rate: optional string, containing an integer, at least 1
	    Maximum allowed bandwidth, in bit/s.  Optional.  If  specified,  the
	    queue's rate will not be allowed to exceed the specified value, even
	    if	excess	bandwidth  is  available. If unspecified, defaults to no
	    limit.

   Common Columns:

     The overall purpose of these columns is described under Common  Columns  at
     the beginning of this document.

     other_config: map of string-string pairs

     external_ids: map of string-string pairs

Mirror TABLE
     A port mirror within a Bridge.

     A port mirror configures a bridge to send selected frames to special ``mir-
     rored''  ports, in addition to their normal destinations. Mirroring traffic
     may also be referred to as SPAN or RSPAN, depending  on  how  the	mirrored
     traffic is sent.

     When  a  packet enters an Open vSwitch bridge, it becomes eligible for mir-
     roring based on its ingress port and VLAN. As the	packet	travels  through
     the  flow tables, each time it is output to a port, it becomes eligible for
     mirroring based on the egress port and VLAN. In Open vSwitch 2.5 and later,
     mirroring occurs just after a packet  first  becomes  eligible,  using  the
     packet as it exists at that point; in Open vSwitch 2.4 and earlier, mirror-
     ing occurs only after a packet has traversed all the flow tables, using the
     original packet as it entered the bridge. This makes a difference only when
     the  flow table modifies the packet: in Open vSwitch 2.4, the modifications
     are never visible to mirrors, whereas in Open vSwitch 2.5 and later modifi-
     cations made before the first output that makes it eligible  for  mirroring
     to a particular destination are visible.

     A	packet	that  enters  an Open vSwitch bridge is mirrored to a particular
     destination only once, even if it is eligible for multiple reasons. For ex-
     ample, a packet would be mirrored to a particular	output_port  only  once,
     even  if  it  is selected for mirroring to that port by select_dst_port and
     select_src_port in the same or different Mirror records.

   Summary:
     name			   string
     Selecting Packets for Mirroring:
       select_all		   boolean
       select_dst_port		   set of weak reference to Ports
       select_src_port		   set of weak reference to Ports
       select_vlan		   set of up to 4,096 integers, in  range  0  to
				   4,095
     Mirroring Destination Configuration:
       output_port		   optional weak reference to Port
       output_vlan		   optional integer, in range 1 to 4,095
       snaplen			   optional integer, in range 14 to 65,535
     Statistics: Mirror counters:
       statistics : tx_packets	   optional integer
       statistics : tx_bytes	   optional integer
     Common Columns:
       external_ids		   map of string-string pairs

   Details:
     name: string
	    Arbitrary identifier for the Mirror.

   Selecting Packets for Mirroring:

     To be selected for mirroring, a given packet must enter or leave the bridge
     through a selected port and it must also be in one of the selected VLANs.

     select_all: boolean
	    If	true, every packet arriving or departing on any port is selected
	    for mirroring.

     select_dst_port: set of weak reference to Ports
	    Ports on which departing packets are selected for mirroring.

     select_src_port: set of weak reference to Ports
	    Ports on which arriving packets are selected for mirroring.

     select_vlan: set of up to 4,096 integers, in range 0 to 4,095
	    VLANs on which packets are selected for mirroring. An empty set  se-
	    lects packets on all VLANs.

   Mirroring Destination Configuration:

     These columns are mutually exclusive. Exactly one of them must be nonempty.

     output_port: optional weak reference to Port
	    Output port for selected packets, if nonempty.

	    Specifying	a  port for mirror output reserves that port exclusively
	    for mirroring. No frames other than those selected for mirroring via
	    this column will be forwarded to the port, and any	frames	received
	    on the port will be discarded.

	    The  output  port may be any kind of port supported by Open vSwitch.
	    It may be, for example, a physical port (sometimes called SPAN) or a
	    GRE tunnel.

     output_vlan: optional integer, in range 1 to 4,095
	    Output VLAN for selected packets, if nonempty.

	    The frames will be sent out all ports  that  trunk	output_vlan,  as
	    well  as  any  ports with implicit VLAN output_vlan. When a mirrored
	    frame is sent out a trunk port, the frame's VLAN tag will be set  to
	    output_vlan,  replacing any existing tag; when it is sent out an im-
	    plicit VLAN port, the frame will not be tagged. This type of mirror-
	    ing is sometimes called RSPAN.

	    See the documentation for other_config:forward-bpdu in the Interface
	    table for a list of destination MAC addresses which will not be mir-
	    rored to a VLAN to avoid confusing switches that interpret the  pro-
	    tocols that they represent.

	    Please note: Mirroring to a VLAN can disrupt a network that contains
	    unmanaged  switches.  Consider an unmanaged physical switch with two
	    ports: port 1, connected to an end host, and port 2, connected to an
	    Open vSwitch configured to mirror received packets into VLAN 123  on
	    port  2. Suppose that the end host sends a packet on port 1 that the
	    physical switch forwards to port 2. The Open vSwitch  forwards  this
	    packet  to	its  destination  and then reflects it back on port 2 in
	    VLAN 123. This reflected packet causes the unmanaged physical switch
	    to replace the MAC learning table entry, which correctly pointed  to
	    port  1,  with one that incorrectly points to port 2. Afterward, the
	    physical switch will direct packets destined for the end host to the
	    Open vSwitch on port 2, instead of to the end host on port	1,  dis-
	    rupting connectivity. If mirroring to a VLAN is desired in this sce-
	    nario,  then the physical switch must be replaced by one that learns
	    Ethernet addresses on a per-VLAN basis. In addition, learning should
	    be disabled on the VLAN containing mirrored traffic. If this is  not
	    done  then	intermediate switches will learn the MAC address of each
	    end host from the mirrored traffic. If packets being  sent	to  that
	    end  host  are  also  mirrored,  then they will be dropped since the
	    switch will attempt to send  them  out  the  input	port.  Disabling
	    learning  for  the	VLAN will cause the switch to correctly send the
	    packet out all ports configured for that VLAN. If  Open  vSwitch  is
	    being  used  as  an intermediate switch, learning can be disabled by
	    adding the mirrored VLAN to flood_vlans in	the  appropriate  Bridge
	    table or tables.

	    Mirroring to a GRE tunnel has fewer caveats than mirroring to a VLAN
	    and should generally be preferred.

     snaplen: optional integer, in range 14 to 65,535
	    Maximum per-packet number of bytes to mirror.

	    A mirrored packet with size larger than snaplen will be truncated in
	    datapath  to snaplen bytes before sending to the mirror output port.
	    If omitted, packets are not truncated.

   Statistics: Mirror counters:

     Key-value pairs that report mirror statistics. The update	period	is  con-
     trolled by other_config:stats-update-interval in the Open_vSwitch table.

     statistics : tx_packets: optional integer
	    Number of packets transmitted through this mirror.

     statistics : tx_bytes: optional integer
	    Number of bytes transmitted through this mirror.

   Common Columns:

     The  overall  purpose of these columns is described under Common Columns at
     the beginning of this document.

     external_ids: map of string-string pairs

Controller TABLE
     An OpenFlow controller.

   Summary:
     Core Features:
       type			   optional string, either primary or service
       target			   string
       connection_mode		   optional   string,	 either    in-band    or
				   out-of-band
     Controller Failure Detection and Handling:
       max_backoff		   optional integer, at least 1,000
       inactivity_probe 	   optional integer
     Asynchronous Messages:
       enable_async_messages	   optional boolean
       Controller Rate Limiting:
	  controller_queue_size    optional integer, in range 1 to 512
	  controller_rate_limit    optional integer, at least 100
	  controller_burst_limit   optional integer, at least 25
	  Controller Rate Limiting Statistics:
	    status : packet-in-TYPE-bypassed
				   optional  string,  containing  an integer, at
				   least 0
	    status : packet-in-TYPE-queued
				   optional string, containing	an  integer,  at
				   least 0
	    status : packet-in-TYPE-dropped
				   optional  string,  containing  an integer, at
				   least 0
	    status : packet-in-TYPE-backlog
				   optional string, containing	an  integer,  at
				   least 0
     Additional In-Band Configuration:
       local_ip 		   optional string
       local_netmask		   optional string
       local_gateway		   optional string
     Controller Status:
       is_connected		   boolean
       role			   optional  string,  one  of  master, other, or
				   slave
       status : last_error	   optional string
       status : state		   optional string, one of ACTIVE, BACKOFF, CON-
				   NECTING, IDLE, or VOID
       status : sec_since_connect
				   optional string, containing	an  integer,  at
				   least 0
       status : sec_since_disconnect
				   optional  string,  containing  an integer, at
				   least 1
     Connection Parameters:
       other_config : dscp	   optional string, containing an integer
     Common Columns:
       external_ids		   map of string-string pairs
       other_config		   map of string-string pairs

   Details:
   Core Features:

     type: optional string, either primary or service
	    Open vSwitch supports two kinds of OpenFlow  controllers.  A  bridge
	    may have any number of each kind:

	    Primary controllers
		   This  is  the  kind	of controller envisioned by the OpenFlow
		   specifications. Usually, a primary  controller  implements  a
		   network policy by taking charge of the switch's flow table.

		   The	fail_mode  column in the Bridge table applies to primary
		   controllers.

		   When  multiple  primary  controllers  are  configured,   Open
		   vSwitch connects to all of them simultaneously. OpenFlow pro-
		   vides few facilities to allow multiple controllers to coordi-
		   nate  in  interacting  with a single switch, so more than one
		   primary controller should  be  specified  only  if  the  con-
		   trollers  are  themselves  designed	to  coordinate with each
		   other.

	    Service controllers
		   These kinds of OpenFlow controller connections  are	intended
		   for	 occasional  support  and  maintenance	use,  e.g.  with
		   ovs-ofctl. Usually a service controller connects only briefly
		   to inspect or modify some of a switch's state.

		   The fail_mode column in the Bridge table does  not  apply  to
		   service controllers.

	    By	default,  Open vSwitch treats controllers with active connection
	    methods as primary controllers and	those  with  passive  connection
	    methods  as service controllers. Set this column to the desired type
	    to override this default.

     target: string
	    Connection method for controller.

	    The following active connection methods are currently supported:

	    ssl:host[:port]
		   The specified SSL port on the host at the given  host,  which
		   can	either	be a DNS name (if built with unbound library) or
		   an IP address. The ssl column in the Open_vSwitch table  must
		   point to a valid SSL configuration when this form is used.

		   If port is not specified, it defaults to 6653.

		   SSL	support  is an optional feature that is not always built
		   as part of Open vSwitch.

	    tcp:host[:port]
		   The specified TCP port on the host at the given  host,  which
		   can	either	be a DNS name (if built with unbound library) or
		   an IP address (IPv4 or IPv6). If host  is  an  IPv6	address,
		   wrap it in square brackets, e.g. tcp:[::1]:6653.

		   If port is not specified, it defaults to 6653.

	    The following passive connection methods are currently supported:

	    pssl:[port][:host]
		   Listens  for  SSL  connections  on the specified TCP port. If
		   host, which can either be a DNS name (if built  with  unbound
		   library) or an IP address, is specified, then connections are
		   restricted to the resolved or specified local IP address (ei-
		   ther  IPv4  or  IPv6). If host is an IPv6 address, wrap it in
		   square brackets, e.g. pssl:6653:[::1].

		   If port is not specified, it defaults to 6653. If host is not
		   specified then it listens only on IPv4  (but  not  IPv6)  ad-
		   dresses.  The ssl column in the Open_vSwitch table must point
		   to a valid SSL configuration when this form is used.

		   If port is not specified, it currently to 6653.

		   SSL support is an optional feature that is not  always  built
		   as part of Open vSwitch.

	    ptcp:[port][:host]
		   Listens  for  connections on the specified TCP port. If host,
		   which can either be a DNS name (if  built  with  unbound  li-
		   brary)  or  an IP address, is specified, then connections are
		   restricted to the resolved or specified local IP address (ei-
		   ther IPv4 or IPv6). If host is an IPv6 address,  wrap  it  in
		   square  brackets, e.g. ptcp:6653:[::1]. If host is not speci-
		   fied then it listens only on IPv4 addresses.

		   If port is not specified, it defaults to 6653.

	    When multiple controllers are configured for a  single  bridge,  the
	    target values must be unique. Duplicate target values yield unspeci-
	    fied results.

     connection_mode: optional string, either in-band or out-of-band
	    If	it  is	specified,  this  setting  must  be one of the following
	    strings that describes how Open vSwitch contacts this OpenFlow  con-
	    troller over the network:

	    in-band
		   In this mode, this controller's OpenFlow traffic travels over
		   the bridge associated with the controller. With this setting,
		   Open  vSwitch  allows  traffic to and from the controller re-
		   gardless of the contents of the OpenFlow flow table.  (Other-
		   wise, Open vSwitch would never be able to connect to the con-
		   troller,  because  it did not have a flow to enable it.) This
		   is the most common connection mode because it is  not  neces-
		   sary to maintain two independent networks.

	    out-of-band
		   In  this  mode, OpenFlow traffic uses a control network sepa-
		   rate from the bridge associated with  this  controller,  that
		   is, the bridge does not use any of its own network devices to
		   communicate	with the controller. The control network must be
		   configured  separately,  before  or	after  ovs-vswitchd   is
		   started.

	    If not specified, the default is implementation-specific.

   Controller Failure Detection and Handling:

     max_backoff: optional integer, at least 1,000
	    Maximum  number of milliseconds to wait between connection attempts.
	    Default is implementation-specific.

     inactivity_probe: optional integer
	    Maximum number of milliseconds of idle time on  connection	to  con-
	    troller  before sending an inactivity probe message. If Open vSwitch
	    does not communicate with the controller for the specified number of
	    seconds, it will send a probe. If a response is not received for the
	    same additional amount of time, Open vSwitch assumes the  connection
	    has  been  broken  and attempts to reconnect. Default is implementa-
	    tion-specific. A value of 0 disables inactivity probes.

   Asynchronous Messages:

     OpenFlow switches send certain messages to controllers spontanenously, that
     is, not in response to any request from the controller. These messages  are
     called ``asynchronous messages.'' These columns allow asynchronous messages
     to be limited or disabled to ensure the best use of network resources.

     enable_async_messages: optional boolean
	    The  OpenFlow protocol enables asynchronous messages at time of con-
	    nection establishment, which means that  a	controller  can  receive
	    asynchronous  messages,  potentially  many of them, even if it turns
	    them off immediately after connecting. Set this column to  false  to
	    change  Open  vSwitch behavior to disable, by default, all asynchro-
	    nous messages.  The  controller  can  use  the  NXT_SET_ASYNC_CONFIG
	    Nicira  extension  to  OpenFlow to turn on any messages that it does
	    want to receive, if any.

   Controller Rate Limiting:

     A switch can forward packets to a controller over	the  OpenFlow  protocol.
     Forwarding  packets this way at too high a rate can overwhelm a controller,
     frustrate use of the OpenFlow connection for other purposes,  increase  the
     latency  of flow setup, and use an unreasonable amount of bandwidth. There-
     fore, Open vSwitch supports limiting the rate of  packet  forwarding  to  a
     controller.

     There  are  two  main reasons in OpenFlow for a packet to be sent to a con-
     troller: either the packet ``misses'' in the flow table, that is, there  is
     no  matching  flow,  or  a flow table action says to send the packet to the
     controller. Open vSwitch limits the rate of each kind of packet  separately
     at the configured rate. Therefore, the actual rate that packets are sent to
     the  controller  can  be  up to twice the configured rate, when packets are
     sent for both reasons.

     This feature is specific to forwarding packets over an OpenFlow connection.
     It is not general-purpose QoS. See the QoS table  for  quality  of  service
     configuration, and ingress_policing_rate in the Interface table for ingress
     policing configuration.

     controller_queue_size: optional integer, in range 1 to 512
	    This  sets	the maximum size of the queue of packets that need to be
	    sent to this OpenFlow controller. The value must be less  than  512.
	    If	not specified the queue size is limited to the value set for the
	    management	controller  in	 other_config:controller-queue-size   if
	    present  or  100 packets by default. Note: increasing the queue size
	    might have a negative impact on latency.

     controller_rate_limit: optional integer, at least 100
	    The maximum rate at which the switch will  forward	packets  to  the
	    OpenFlow  controller,  in  packets per second. If no value is speci-
	    fied, rate limiting is disabled.

     controller_burst_limit: optional integer, at least 25
	    When a high rate triggers rate-limiting, Open vSwitch queues packets
	    to the controller for each port and transmits them to the controller
	    at the configured rate. This value limits the number of queued pack-
	    ets. Ports on a bridge share the packet queue fairly.

	    This value has no effect unless controller_rate_limit is configured.
	    The current default when this value is not specified is  one-quarter
	    of	controller_rate_limit, meaning that queuing can delay forwarding
	    a packet to the controller by up to 250 ms.

   Controller Rate Limiting Statistics:

     These values report the effects of rate limiting. Their values are relative
     to establishment of the most recent OpenFlow connection, or since rate lim-
     iting was enabled, whichever happened more recently. Each consists  of  two
     values, one with TYPE replaced by miss for rate limiting flow table misses,
     and  the  other with TYPE replaced by action for rate limiting packets sent
     by OpenFlow actions.

     These statistics are reported only when controller  rate  limiting  is  en-
     abled.

     status : packet-in-TYPE-bypassed: optional string, containing an integer,
     at least 0
	    Number  of packets sent directly to the controller, without queuing,
	    because the rate did not exceed the configured maximum.

     status : packet-in-TYPE-queued: optional string, containing an integer, at
     least 0
	    Number of packets added to the queue to send later.

     status : packet-in-TYPE-dropped: optional string, containing an integer, at
     least 0
	    Number of packets added to the queue that were later dropped due  to
	    overflow. This value is less than or equal to status:packet-in-TYPE-
	    queued.

     status : packet-in-TYPE-backlog: optional string, containing an integer, at
     least 0
	    Number  of	packets  currently queued. The other statistics increase
	    monotonically, but this  one  fluctuates  between  0  and  the  con-
	    troller_burst_limit as conditions change.

   Additional In-Band Configuration:

     These  values  are  considered  only  in  in-band control mode (see connec-
     tion_mode).

     When multiple controllers are configured on a single bridge,  there  should
     be  only one set of unique values in these columns. If different values are
     set for these columns in different controllers, the effect is unspecified.

     local_ip: optional string
	    The IP address to configure on the local port,  e.g.  192.168.0.123.
	    If this value is unset, then local_netmask and local_gateway are ig-
	    nored.

     local_netmask: optional string
	    The  IP  netmask to configure on the local port, e.g. 255.255.255.0.
	    If local_ip is set but this value is unset, then the default is cho-
	    sen based on whether the IP address is class A, B, or C.

     local_gateway: optional string
	    The IP address of the gateway to configure on the local port,  as  a
	    string,  e.g.  192.168.0.1.  Leave this column unset if this network
	    has no gateway.

   Controller Status:

     is_connected: boolean
	    true if currently connected to this controller, false otherwise.

     role: optional string, one of master, other, or slave
	    The level of authority this controller has on the associated bridge.
	    Possible values are:

	    other  Allows the controller access to all OpenFlow features.

	    master
		   Equivalent to other, except that there may  be  at  most  one
		   such controller at a time. If a given controller promotes it-
		   self  to  this  role,  ovs-vswitchd demotes any existing con-
		   troller with the role to slave.

	    slave  Allows the controller read-only access to OpenFlow  features.
		   Attempts  to  modify  the flow table will be rejected with an
		   error. Such controllers  do	not  receive  OFPT_PACKET_IN  or
		   OFPT_FLOW_REMOVED	messages,    but    they    do	 receive
		   OFPT_PORT_STATUS messages.

     status : last_error: optional string
	    A human-readable description of the last error on the connection  to
	    the controller; i.e. strerror(errno). This key will exist only if an
	    error has occurred.

     status : state: optional string, one of ACTIVE, BACKOFF, CONNECTING, IDLE,
     or VOID
	    The state of the connection to the controller:

	    VOID   Connection is disabled.

	    BACKOFF
		   Attempting to reconnect at an increasing period.

	    CONNECTING
		   Attempting to connect.

	    ACTIVE
		   Connected, remote host responsive.

	    IDLE   Connection is idle. Waiting for response to keep-alive.

	    These  values  may	change in the future. They are provided only for
	    human consumption.

     status : sec_since_connect: optional string, containing an integer, at
     least 0
	    The amount of time since this controller last successfully connected
	    to the switch (in seconds). Value is empty if controller  has  never
	    successfully connected.

     status : sec_since_disconnect: optional string, containing an integer, at
     least 1
	    The  amount of time since this controller last disconnected from the
	    switch (in seconds). Value is empty if controller has never  discon-
	    nected.

   Connection Parameters:

     Additional  configuration	for  a connection between the controller and the
     Open vSwitch.

     other_config : dscp: optional string, containing an integer
	    The Differentiated Service Code Point (DSCP) is  specified	using  6
	    bits  in the Type of Service (TOS) field in the IP header. DSCP pro-
	    vides a mechanism to classify the network traffic and provide  Qual-
	    ity  of  Service (QoS) on IP networks. The DSCP value specified here
	    is used when establishing the connection between the controller  and
	    the Open vSwitch. If no value is specified, a default value of 48 is
	    chosen. Valid DSCP values must be in the range 0 to 63.

   Common Columns:

     The  overall  purpose of these columns is described under Common Columns at
     the beginning of this document.

     external_ids: map of string-string pairs

     other_config: map of string-string pairs

Manager TABLE
     Configuration for a database connection to an Open vSwitch database (OVSDB)
     client.

     This table primarily configures the Open vSwitch  database  (ovsdb-server),
     not  the Open vSwitch switch (ovs-vswitchd). The switch does read the table
     to determine what connections should be treated as in-band.

     The Open vSwitch database server can initiate and maintain  active  connec-
     tions to remote clients. It can also listen for database connections.

   Summary:
     Core Features:
       target			   string (must be unique within table)
       connection_mode		   optional    string,	  either    in-band   or
				   out-of-band
     Client Failure Detection and Handling:
       max_backoff		   optional integer, at least 1,000
       inactivity_probe 	   optional integer
     Status:
       is_connected		   boolean
       status : last_error	   optional string
       status : state		   optional string, one of ACTIVE, BACKOFF, CON-
				   NECTING, IDLE, or VOID
       status : sec_since_connect
				   optional string, containing	an  integer,  at
				   least 0
       status : sec_since_disconnect
				   optional  string,  containing  an integer, at
				   least 0
       status : locks_held	   optional string
       status : locks_waiting	   optional string
       status : locks_lost	   optional string
       status : n_connections	   optional string, containing	an  integer,  at
				   least 2
       status : bound_port	   optional string, containing an integer
     Connection Parameters:
       other_config : dscp	   optional string, containing an integer
     Common Columns:
       external_ids		   map of string-string pairs
       other_config		   map of string-string pairs

   Details:
   Core Features:

     target: string (must be unique within table)
	    Connection method for managers.

	    The following connection methods are currently supported:

	    ssl:host[:port]
		   The	specified  SSL port on the host at the given host, which
		   can either be a DNS name (if built with unbound  library)  or
		   an  IP address. The ssl column in the Open_vSwitch table must
		   point to a valid SSL configuration when this form is used.

		   If port is not specified, it defaults to 6640.

		   SSL support is an optional feature that is not  always  built
		   as part of Open vSwitch.

	    tcp:host[:port]
		   The	specified  TCP port on the host at the given host, which
		   can either be a DNS name (if built with unbound  library)  or
		   an  IP  address  (IPv4  or IPv6). If host is an IPv6 address,
		   wrap it in square brackets, e.g. tcp:[::1]:6640.

		   If port is not specified, it defaults to 6640.

	    pssl:[port][:host]
		   Listens for SSL connections on the specified TCP port.  Spec-
		   ify	0  for	port  to have the kernel automatically choose an
		   available port. If host, which can either be a DNS  name  (if
		   built  with	unbound library) or an IP address, is specified,
		   then connections are restricted to the resolved or  specified
		   local IP address (either IPv4 or IPv6 address). If host is an
		   IPv6  address, wrap in square brackets, e.g. pssl:6640:[::1].
		   If host is not specified then it listens only  on  IPv4  (but
		   not IPv6) addresses. The ssl column in the Open_vSwitch table
		   must  point	to  a  valid SSL configuration when this form is
		   used.

		   If port is not specified, it defaults to 6640.

		   SSL support is an optional feature that is not  always  built
		   as part of Open vSwitch.

	    ptcp:[port][:host]
		   Listens  for connections on the specified TCP port. Specify 0
		   for port to have the kernel automatically choose an available
		   port. If host, which can either be a DNS name (if built  with
		   unbound library) or an IP address, is specified, then connec-
		   tions  are  restricted  to the resolved or specified local IP
		   address (either IPv4 or IPv6 address). If host is an IPv6 ad-
		   dress, wrap it in square brackets, e.g.  ptcp:6640:[::1].  If
		   host is not specified then it listens only on IPv4 addresses.

		   If port is not specified, it defaults to 6640.

	    When  multiple  managers  are  configured, the target values must be
	    unique. Duplicate target values yield unspecified results.

     connection_mode: optional string, either in-band or out-of-band
	    If it is specified, this  setting  must  be  one  of  the  following
	    strings  that  describes how Open vSwitch contacts this OVSDB client
	    over the network:

	    in-band
		   In this mode, this connection's traffic travels over a bridge
		   managed by Open vSwitch. With this setting, Open vSwitch  al-
		   lows  traffic  to  and from the client regardless of the con-
		   tents of the OpenFlow flow table.  (Otherwise,  Open  vSwitch
		   would  never be able to connect to the client, because it did
		   not have a flow to enable it.) This is the most  common  con-
		   nection  mode because it is not necessary to maintain two in-
		   dependent networks.

	    out-of-band
		   In this mode, the client's traffic  uses  a	control  network
		   separate  from  that  managed  by Open vSwitch, that is, Open
		   vSwitch does not use any of its own network devices to commu-
		   nicate with the client. The control network must  be  config-
		   ured separately, before or after ovs-vswitchd is started.

	    If not specified, the default is implementation-specific.

   Client Failure Detection and Handling:

     max_backoff: optional integer, at least 1,000
	    Maximum  number of milliseconds to wait between connection attempts.
	    Default is implementation-specific.

     inactivity_probe: optional integer
	    Maximum number of milliseconds of idle time  on  connection  to  the
	    client  before  sending an inactivity probe message. If Open vSwitch
	    does not communicate with the client for  the  specified  number  of
	    seconds, it will send a probe. If a response is not received for the
	    same  additional amount of time, Open vSwitch assumes the connection
	    has been broken and attempts to reconnect.	Default  is  implementa-
	    tion-specific. A value of 0 disables inactivity probes.

   Status:

     Key-value	pair of is_connected is always updated. Other key-value pairs in
     the status columns may be updated depends on the target type.

     When target specifies a connection method that listens for inbound  connec-
     tions  (e.g. ptcp: or punix:), both n_connections and is_connected may also
     be updated while the remaining key-value pairs are omitted.

     On the other hand, when target specifies an outbound connection,  all  key-
     value  pairs may be updated, except the above-mentioned two key-value pairs
     associated with inbound connection targets. They are omitted.

     is_connected: boolean
	    true if currently connected to this manager, false otherwise.

     status : last_error: optional string
	    A human-readable description of the last error on the connection  to
	    the  manager;  i.e.  strerror(errno). This key will exist only if an
	    error has occurred.

     status : state: optional string, one of ACTIVE, BACKOFF, CONNECTING, IDLE,
     or VOID
	    The state of the connection to the manager:

	    VOID   Connection is disabled.

	    BACKOFF
		   Attempting to reconnect at an increasing period.

	    CONNECTING
		   Attempting to connect.

	    ACTIVE
		   Connected, remote host responsive.

	    IDLE   Connection is idle. Waiting for response to keep-alive.

	    These values may change in the future. They are  provided  only  for
	    human consumption.

     status : sec_since_connect: optional string, containing an integer, at
     least 0
	    The amount of time since this manager last successfully connected to
	    the  database (in seconds). Value is empty if manager has never suc-
	    cessfully connected.

     status : sec_since_disconnect: optional string, containing an integer, at
     least 0
	    The amount of time since this manager  last  disconnected  from  the
	    database  (in  seconds). Value is empty if manager has never discon-
	    nected.

     status : locks_held: optional string
	    Space-separated list of the names of OVSDB locks that the connection
	    holds. Omitted if the connection does not hold any locks.

     status : locks_waiting: optional string
	    Space-separated list of the names of OVSDB locks that the connection
	    is currently waiting to acquire. Omitted if the  connection  is  not
	    waiting for any locks.

     status : locks_lost: optional string
	    Space-separated list of the names of OVSDB locks that the connection
	    has  had  stolen  by  another OVSDB client. Omitted if no locks have
	    been stolen from this connection.

     status : n_connections: optional string, containing an integer, at least 2
	    When target specifies a connection method that listens  for  inbound
	    connections  (e.g.	ptcp:  or pssl:) and more than one connection is
	    actually active, the value is the number of active connections. Oth-
	    erwise, this key-value pair is omitted.

     status : bound_port: optional string, containing an integer
	    When target is ptcp: or pssl:, this is the TCP  port  on  which  the
	    OVSDB  server is listening. (This is particularly useful when target
	    specifies a port of 0, allowing the kernel to choose  any  available
	    port.)

   Connection Parameters:

     Additional  configuration for a connection between the manager and the Open
     vSwitch Database.

     other_config : dscp: optional string, containing an integer
	    The Differentiated Service Code Point (DSCP) is  specified	using  6
	    bits  in the Type of Service (TOS) field in the IP header. DSCP pro-
	    vides a mechanism to classify the network traffic and provide  Qual-
	    ity  of  Service (QoS) on IP networks. The DSCP value specified here
	    is used when establishing the connection between the manager and the
	    Open vSwitch. If no value is specified, a default  value  of  48  is
	    chosen. Valid DSCP values must be in the range 0 to 63.

   Common Columns:

     The  overall  purpose of these columns is described under Common Columns at
     the beginning of this document.

     external_ids: map of string-string pairs

     other_config: map of string-string pairs

NetFlow TABLE
     A NetFlow target. NetFlow is a protocol that exports a  number  of  details
     about terminating IP flows, such as the principals involved and duration.

   Summary:
     targets			   set of 1 or more strings
     engine_id			   optional integer, in range 0 to 255
     engine_type		   optional integer, in range 0 to 255
     active_timeout		   integer, at least -1
     add_id_to_interface	   boolean
     Common Columns:
       external_ids		   map of string-string pairs

   Details:
     targets: set of 1 or more strings
	    NetFlow targets in the form ip:port. The ip must be specified numer-
	    ically, not as a DNS name.

     engine_id: optional integer, in range 0 to 255
	    Engine  ID to use in NetFlow messages. Defaults to datapath index if
	    not specified.

     engine_type: optional integer, in range 0 to 255
	    Engine type to use in NetFlow messages. Defaults to  datapath  index
	    if not specified.

     active_timeout: integer, at least -1
	    The  interval  at  which NetFlow records are sent for flows that are
	    still active, in seconds. A value of 0 requests the default  timeout
	    (currently 600 seconds); a value of -1 disables active timeouts.

	    The  NetFlow passive timeout, for flows that become inactive, is not
	    configurable. It will vary depending on the  Open  vSwitch	version,
	    the  forms	and contents of the OpenFlow flow tables, CPU and memory
	    usage, and network activity. A typical passive timeout  is	about  a
	    second.

     add_id_to_interface: boolean
	    If	this  column's	value is false, the ingress and egress interface
	    fields of NetFlow flow records are derived from OpenFlow  port  num-
	    bers.  When  it is true, the 7 most significant bits of these fields
	    will be replaced by the least significant 7 bits of the  engine  id.
	    This  is useful because many NetFlow collectors do not expect multi-
	    ple switches to be sending messages from the same host, so	they  do
	    not store the engine information which could be used to disambiguate
	    the traffic.

	    When this option is enabled, a maximum of 508 ports are supported.

   Common Columns:

     The  overall  purpose of these columns is described under Common Columns at
     the beginning of this document.

     external_ids: map of string-string pairs

Datapath TABLE
     Configuration for a datapath within Open_vSwitch.

     A datapath is  responsible  for  providing  the  packet  handling	in  Open
     vSwitch.  There  are  two	primary  datapath  implementations  used by Open
     vSwitch: kernel and userspace. Kernel datapath implementations  are  avail-
     able  for	Linux  and  Hyper-V, and selected as system in the datapath_type
     column of the Bridge table. The userspace datapath is used by DPDK and  AF-
     XDP,  and	is  selected as netdev in the datapath_type column of the Bridge
     table.

     A datapath of a particular type is shared by all the bridges that use  that
     datapath.	Thus,  configurations  applied	to this table affect all bridges
     that use this datapath.

   Summary:
     datapath_version		   string
     ct_zones			   map of integer-CT_Zone pairs, key in range  0
				   to 65,535
     Capabilities:
       capabilities : max_vlan_headers
				   optional  string,  containing  an integer, at
				   least 0
       capabilities : recirc	   optional string, either true or false
       capabilities : lb_output_action
				   optional string, either true or false
       Connection-Tracking Capabilities:
	  capabilities : ct_state  optional string, either true or false
	  capabilities : ct_state_nat
				   optional string, either true or false
	  capabilities : ct_zone   optional string, either true or false
	  capabilities : ct_mark   optional string, either true or false
	  capabilities : ct_label  optional string, either true or false
	  capabilities : ct_orig_tuple
				   optional string, either true or false
	  capabilities : ct_orig_tuple6
				   optional string, either true or false
       capabilities : masked_set_action
				   optional string, either true or false
       capabilities : tnl_push_pop
				   optional string, either true or false
       capabilities : ufid	   optional string, either true or false
       capabilities : trunc	   optional string, either true or false
       capabilities : nd_ext	   optional string, either true or false
       Clone Actions:
	  capabilities : clone	   optional string, either true or false
	  capabilities : sample_nesting
				   optional string, containing	an  integer,  at
				   least 0
       capabilities : ct_eventmask
				   optional string, either true or false
       capabilities : ct_clear	   optional string, either true or false
       capabilities : max_hash_alg
				   optional  string,  containing  an integer, at
				   least 0
       capabilities : check_pkt_len
				   optional string, either true or false
       capabilities : ct_timeout   optional string, either true or false
       capabilities : explicit_drop_action
				   optional string, either true or false
       capabilities : ct_zero_snat
				   optional string, either true or false
     Common Columns:
       external_ids		   map of string-string pairs

   Details:
     datapath_version: string
	    Reports the version number of the Open vSwitch datapath in use. This
	    allows management software to detect and  report  discrepancies  be-
	    tween Open vSwitch userspace and datapath versions. (The ovs_version
	    column  in	the Open_vSwitch reports the Open vSwitch userspace ver-
	    sion.) The version reported depends on the datapath in use:

	    *	   When the kernel module included in the  Open  vSwitch  source
		   tree  is  used,  this column reports the Open vSwitch version
		   from which the module was taken.

	    *	   When the kernel module that is part	of  the  upstream  Linux
		   kernel is used, this column reports <unknown>.

	    *	   When the datapath is built into the ovs-vswitchd binary, this
		   column  reports <built-in>. A built-in datapath is by defini-
		   tion the same version as the rest of the Open  vSwitch  user-
		   space.

	    *	   Other  datapaths  (such  as the Hyper-V kernel datapath) cur-
		   rently report <unknown>.

	    A version discrepancy between ovs-vswitchd and the datapath  in  use
	    is	not  normally cause for alarm. The Open vSwitch kernel datapaths
	    for Linux and Hyper-V, in particular, are designed for  maximum  in-
	    ter-version compatibility: any userspace version works with with any
	    kernel  version.  Some  reasons  do  exist	to  insist on particular
	    user/kernel pairings. First, newer kernel versions add new features,
	    that can only be used by new-enough userspace, e.g. VXLAN  tunneling
	    requires  certain  minimal userspace and kernel versions. Second, as
	    an extension to the first reason, some newer kernel versions add new
	    features for enhancing performance that  only  new-enough  userspace
	    versions can take advantage of.

     ct_zones: map of integer-CT_Zone pairs, key in range 0 to 65,535
	    Configuration  for	connection tracking zones. Each pair maps from a
	    zone id to a configuration for that zone. Zone 0 applies to the  de-
	    fault  zone  (ie, the one used if a zone is not specified in connec-
	    tion tracking-related OpenFlow matches and actions).

   Capabilities:

     The capabilities column reports a datapath's features. For the netdev data-
     path, the capabilities are fixed for a given version of  Open  vSwitch  be-
     cause this datapath is built into the ovs-vswitchd binary. The Linux kernel
     and  Windows  and other datapaths, which are external to OVS userspace, can
     vary in version and capabilities independently from ovs-vswitchd.

     Some of these features indicate whether higher-level Open vSwitch	features
     are  available.  For example, OpenFlow features for connection-tracking are
     available only when capabilities:ct_state is true. A controller that wishes
     to determine whether a feature is supported could, therefore,  consult  the
     relevant capabilities in this table. However, as a general rule, it is bet-
     ter for a controller to try to use the higher-level feature and use the re-
     sult as an indication of support, since the low-level capabilities are more
     likely to shift over time than the high-level features that rely on them.

     capabilities : max_vlan_headers: optional string, containing an integer, at
     least 0
	    Number  of	802.1q VLAN headers supported by the datapath, as probed
	    by the ovs-vswitchd slow path. If the datapath  supports  more  VLAN
	    headers  than the slow path, this reports the slow path's limit. The
	    value of other-config:vlan-limit in the Open_vSwitch table does  not
	    influence the number reported here.

     capabilities : recirc: optional string, either true or false
	    If	this is true, then the datapath supports recirculation, specifi-
	    cally OVS_KEY_ATTR_RECIRC_ID. Recirculation enables  higher  perfor-
	    mance for MPLS and active-active load balancing bonding modes.

     capabilities : lb_output_action: optional string, either true or false
	    If	this  is  true, then the datapath supports optimized balance-tcp
	    bond mode. This capability replaces existing hash and recirc actions
	    with new action lb_output and  avoids  recirculation  of  packet  in
	    datapath.  It  is supported only for balance-tcp bond mode in netdev
	    datapath. The new action gives higer performance by using bond buck-
	    ets instead of post recirculation flows for selection of slave  port
	    from bond. By default this new action is disabled, however it can be
	    enabled by setting other-config:lb-output-action in Port table.

   Connection-Tracking Capabilities:

     These  capabilities  are  granular  because  Open vSwitch and its datapaths
     added support for connection tracking over several releases, with	features
     added individually over that time.

     capabilities : ct_state: optional string, either true or false
	    If	true,  datapath  supports OVS_KEY_ATTR_CT_STATE, which indicates
	    support  for  the  bits  in  the  OpenFlow	 ct_state   field   (see
	    ovs-fields(7)) other than snat and dnat, which have a separate capa-
	    bility.

	    If	this is false, the datapath does not support connection-tracking
	    at all and the remaining connection-tracking capabilities should all
	    be false. In this case, Open vSwitch will reject flows that match on
	    the ct_state field or use the ct action.

     capabilities : ct_state_nat: optional string, either true or false
	    If true, it means that the datapath supports the snat and dnat flags
	    in the OpenFlow ct_state field. The ct_state capability must be true
	    for this to make sense.

	    If false, Open vSwitch will reject flows that match on the	snat  or
	    dnat bits in ct_state or use nat in the ct action.

     capabilities : ct_zone: optional string, either true or false
	    If	true,  datapath  supports  OVS_KEY_ATTR_CT_ZONE.  If false, Open
	    vSwitch rejects flows that match on the ct_zone field or that  spec-
	    ify a nonzero zone or a zone field on the ct action.

     capabilities : ct_mark: optional string, either true or false
	    If	true,  datapath  supports  OVS_KEY_ATTR_CT_MARK.  If false, Open
	    vSwitch rejects flows that match on the ct_mark field  or  that  set
	    ct_mark in the ct action.

     capabilities : ct_label: optional string, either true or false
	    If	true,  datapath  supports  OVS_KEY_ATTR_CT_LABEL. If false, Open
	    vSwitch rejects flows that match on the ct_label field or  that  set
	    ct_label in the ct action.

     capabilities : ct_orig_tuple: optional string, either true or false
	    If true, the datapath supports matching the 5-tuple from the connec-
	    tion's  original  direction for IPv4 traffic. If false, Open vSwitch
	    rejects flows that match on ct_nw_src or ct_nw_dst, that use the  ct
	    feature  of  the resubmit action, or the force keyword in the ct ac-
	    tion. (The latter isn't tied to connection tracking support of orig-
	    inal tuples in any technical way. They  are  conflated  because  all
	    current datapaths implemented the two features at the same time.)

	    If this and capabilities:ct_orig_tuple6 are both false, Open vSwitch
	    rejects flows that match on ct_nw_proto, ct_tp_src, or ct_tp_dst.

     capabilities : ct_orig_tuple6: optional string, either true or false
	    If true, the datapath supports matching the 5-tuple from the connec-
	    tion's  original  direction for IPv6 traffic. If false, Open vSwitch
	    rejects flows that match on ct_ipv6_src or ct_ipv6_dst.

     capabilities : masked_set_action: optional string, either true or false
	    True if the datapath supports masked data in OVS_ACTION_ATTR_SET ac-
	    tions. Masked data can improve performance by allowing megaflows  to
	    match on fewer fields.

     capabilities : tnl_push_pop: optional string, either true or false
	    True  if  the  datapath supports tnl_push and pop actions. This is a
	    prerequisite for a datapath to support native tunneling.

     capabilities : ufid: optional string, either true or false
	    True if the datapath supports OVS_FLOW_ATTR_UFID. UFID  support  im-
	    proves  revalidation  performance  by transferring less data between
	    the slow path and the datapath.

     capabilities : trunc: optional string, either true or false
	    True if  the  datapath  supports  OVS_ACTION_ATTR_TRUNC  action.  If
	    false,  the  output  action  with  packet  truncation requires every
	    packet to be sent to the Open vSwitch slow path, which is likely  to
	    make it too slow for mirroring traffic in bulk.

     capabilities : nd_ext: optional string, either true or false
	    True if the datapath supports OVS_KEY_ATTR_ND_EXTENSIONS to match on
	    ICMPv6  "ND  reserved" and "ND option type" header fields. If false,
	    the datapath reports error if the feature is used.

   Clone Actions:

     When Open vSwitch translates actions from OpenFlow into the datapath repre-
     sentation, some of the datapath actions may modify the packet or have other
     side effects that later datapath actions can't undo. The OpenFlow	ct,  me-
     ter,  output  with  truncation,  encap, decap, and dec_nsh_ttl actions fall
     into this category. Often, this is not a problem because nothing  later  on
     needs the original packet.

     Such  actions  can,  however,  occur in circumstances where the translation
     does require the original packet. For example, an	OpenFlow  output  action
     might direct a packet to a patch port, which might in turn lead to a ct ac-
     tion that NATs the packet (which cannot be undone), and then afterward when
     control  flow  pops back across the patch port some other action might need
     to act on the original packet.

     Open vSwitch has two different ways to implement this ``save and  restore''
     via  datapath  actions.  These capabilities indicate which one Open vSwitch
     will choose. When neither is available, Open vSwitch simply fails in situa-
     tions that require this feature.

     capabilities : clone: optional string, either true or false
	    True if the datapath supports OVS_ACTION_ATTR_CLONE action. This  is
	    the  preferred  option for saving and restoring packets, since it is
	    intended for the purpose, but old datapaths do not support it.  Open
	    vSwitch will use it whenever it is available.

	    (The   OpenFlow  clone  action  does  not  always  yield  a  OVS_AC-
	    TION_ATTR_CLONE action. It only does so when the  datapath	supports
	    it and the clone brackets actions that otherwise cannot be undone.)

     capabilities : sample_nesting: optional string, containing an integer, at
     least 0
	    Maximum  level  of nesting allowed by OVS_ACTION_ATTR_SAMPLE action.
	    Open vSwitch misuses this action for saving  and  restoring  packets
	    when the datapath supports more than 3 levels of nesting and OVS_AC-
	    TION_ATTR_CLONE is not available.

     capabilities : ct_eventmask: optional string, either true or false
	    True  if  the  datapath's  OVS_ACTION_ATTR_CT  action implements the
	    OVS_CT_ATTR_EVENTMASK attribute. When this	is  true,  Open  vSwitch
	    uses the event mask feature to limit the kinds of events reported to
	    conntrack  update  listeners.  When  Open  vSwitch doesn't limit the
	    event mask, listeners receive reports of numerous  usually	unimpor-
	    tant  events, such as TCP state machine changes, which can waste CPU
	    time.

     capabilities : ct_clear: optional string, either true or false
	    True if the datapath supports  OVS_ACTION_ATTR_CT_CLEAR  action.  If
	    false, the OpenFlow ct_clear action has no effect on the datapath.

     capabilities : max_hash_alg: optional string, containing an integer, at
     least 0
	    Highest  supported	dp_hash  algorithm.  This allows Open vSwitch to
	    avoid requesting a packet hash that the datapath does not support.

     capabilities : check_pkt_len: optional string, either true or false
	    True if  the  datapath  supports  OVS_ACTION_ATTR_CHECK_PKT_LEN.  If
	    false,  Open vSwitch implements the check_pkt_larger action by send-
	    ing every packet through the Open vSwitch slow path, which is likely
	    to make it too slow for handling traffic in bulk.

     capabilities : ct_timeout: optional string, either true or false
	    True if the datapath supports  OVS_CT_ATTR_TIMEOUT	in  the  OVS_AC-
	    TION_ATTR_CT action. If false, Open vswitch cannot implement timeout
	    policies  based  on connection tracking zones, as configured through
	    the CT_Timeout_Policy table.

     capabilities : explicit_drop_action: optional string, either true or false
	    True if the datapath supports OVS_ACTION_ATTR_DROP.  If  false,  ex-
	    plicit drop action will not be sent to the datapath.

     capabilities : ct_zero_snat: optional string, either true or false
	    True  if the datapath supports all-zero SNAT. This is a special case
	    if	the  src  IP  address  is   configured	 as   all   0's,   i.e.,
	    nat(src=0.0.0.0).  In this case, when a source port collision is de-
	    tected during the commit, the source port will be translated  to  an
	    ephemeral port. If there is no collision, no SNAT is performed.

   Common Columns:

     The  overall  purpose of these columns is described under Common Columns at
     the beginning of this document.

     external_ids: map of string-string pairs

CT_Zone TABLE
     Connection tracking zone configuration

   Summary:
     timeout_policy		   optional CT_Timeout_Policy
     Common Columns:
       external_ids		   map of string-string pairs

   Details:
     timeout_policy: optional CT_Timeout_Policy
	    Connection tracking timeout policy for this zone. If a timeout  pol-
	    icy  is not specified, it defaults to the timeout policy in the sys-
	    tem.

   Common Columns:

     The overall purpose of these columns is described under Common  Columns  at
     the beginning of this document.

     external_ids: map of string-string pairs

CT_Timeout_Policy TABLE
     Connection tracking timeout policy configuration

   Summary:
     Timeouts:
       timeouts 		   map	of  string-integer  pairs,  key  one  of
				   icmp_first,	    icmp_reply,       tcp_close,
				   tcp_close_wait,		tcp_established,
				   tcp_fin_wait,  tcp_last_ack,  tcp_retransmit,
				   tcp_syn_recv,   tcp_syn_sent2,  tcp_syn_sent,
				   tcp_time_wait, tcp_unack, udp_first, udp_mul-
				   tiple, or udp_single, value	in  range  0  to
				   4,294,967,295
       TCP Timeouts:
	  timeouts : tcp_syn_sent  optional integer, in range 0 to 4,294,967,295
	  timeouts : tcp_syn_recv  optional integer, in range 0 to 4,294,967,295
	  timeouts : tcp_established
				   optional integer, in range 0 to 4,294,967,295
	  timeouts : tcp_fin_wait  optional integer, in range 0 to 4,294,967,295
	  timeouts : tcp_close_wait
				   optional integer, in range 0 to 4,294,967,295
	  timeouts : tcp_last_ack  optional integer, in range 0 to 4,294,967,295
	  timeouts : tcp_time_wait
				   optional integer, in range 0 to 4,294,967,295
	  timeouts : tcp_close	   optional integer, in range 0 to 4,294,967,295
	  timeouts : tcp_syn_sent2
				   optional integer, in range 0 to 4,294,967,295
	  timeouts : tcp_retransmit
				   optional integer, in range 0 to 4,294,967,295
	  timeouts : tcp_unack	   optional integer, in range 0 to 4,294,967,295
       UDP Timeouts:
	  timeouts : udp_first	   optional integer, in range 0 to 4,294,967,295
	  timeouts : udp_single    optional integer, in range 0 to 4,294,967,295
	  timeouts : udp_multiple  optional integer, in range 0 to 4,294,967,295
       ICMP Timeouts:
	  timeouts : icmp_first    optional integer, in range 0 to 4,294,967,295
	  timeouts : icmp_reply    optional integer, in range 0 to 4,294,967,295
     Common Columns:
       external_ids		   map of string-string pairs

   Details:
   Timeouts:

     timeouts: map of string-integer pairs, key one of icmp_first, icmp_reply,
     tcp_close, tcp_close_wait, tcp_established, tcp_fin_wait, tcp_last_ack,
     tcp_retransmit, tcp_syn_recv, tcp_syn_sent2, tcp_syn_sent, tcp_time_wait,
     tcp_unack, udp_first, udp_multiple, or udp_single, value in range 0 to
     4,294,967,295
	    The  timeouts column contains key-value pairs used to configure con-
	    nection tracking timeouts in a datapath. Key-value	pairs  that  are
	    not  supported  by	a  datapath are ignored. The timeout value is in
	    seconds.

   TCP Timeouts:

     timeouts : tcp_syn_sent: optional integer, in range 0 to 4,294,967,295
	    The timeout for the connection after the first TCP	SYN  packet  has
	    been seen by conntrack.

     timeouts : tcp_syn_recv: optional integer, in range 0 to 4,294,967,295
	    The timeout of the connection after the first TCP SYN-ACK packet has
	    been seen by conntrack.

     timeouts : tcp_established: optional integer, in range 0 to 4,294,967,295
	    The  timeout  of  the connection after the connection has been fully
	    established.

     timeouts : tcp_fin_wait: optional integer, in range 0 to 4,294,967,295
	    The timeout of the connection after the first  TCP	FIN  packet  has
	    been seen by conntrack.

     timeouts : tcp_close_wait: optional integer, in range 0 to 4,294,967,295
	    The  timeout  of  the  connection after the first TCP ACK packet has
	    been seen after it receives TCP FIN packet.  This  timeout	is  only
	    supported by the Linux kernel datapath.

     timeouts : tcp_last_ack: optional integer, in range 0 to 4,294,967,295
	    The  timeout  of the connection after TCP FIN packets have been seen
	    by conntrack from both directions. This timeout is only supported by
	    the Linux kernel datapath.

     timeouts : tcp_time_wait: optional integer, in range 0 to 4,294,967,295
	    The timeout of the connection after conntrack has seen the	TCP  ACK
	    packet for the second TCP FIN packet.

     timeouts : tcp_close: optional integer, in range 0 to 4,294,967,295
	    The  timeout  of  the  connection after the first TCP RST packet has
	    been seen by conntrack.

     timeouts : tcp_syn_sent2: optional integer, in range 0 to 4,294,967,295
	    The timeout of the connection when only a TCP SYN  packet  has  been
	    seen  by  conntrack  from  both directions (simultaneous open). This
	    timeout is only supported by the Linux kernel datapath.

     timeouts : tcp_retransmit: optional integer, in range 0 to 4,294,967,295
	    The timeout of the connection when it exceeds the maximum number  of
	    retransmissions.  This timeout is only supported by the Linux kernel
	    datapath.

     timeouts : tcp_unack: optional integer, in range 0 to 4,294,967,295
	    The timeout of the connection when non-SYN packets create an  estab-
	    lished  connection	in TCP loose tracking mode. This timeout is only
	    supported by the Linux kernel datapath.

   UDP Timeouts:

     timeouts : udp_first: optional integer, in range 0 to 4,294,967,295
	    The timeout of the connection after the first UDP  packet  has  been
	    seen  by  conntrack. This timeout is only supported by the userspace
	    datapath.

     timeouts : udp_single: optional integer, in range 0 to 4,294,967,295
	    The timeout of the connection when conntrack only  seen  UDP  packet
	    from  the  source  host, but the destination host has never sent one
	    back.

     timeouts : udp_multiple: optional integer, in range 0 to 4,294,967,295
	    The timeout of the connection when UDP packets  have  been	seen  in
	    both directions.

   ICMP Timeouts:

     timeouts : icmp_first: optional integer, in range 0 to 4,294,967,295
	    The  timeout  of the connection after the first ICMP packet has been
	    seen by conntrack.

     timeouts : icmp_reply: optional integer, in range 0 to 4,294,967,295
	    The timeout of the connection when ICMP packets have  been	seen  in
	    both  direction.  This  timeout  is  only supported by the userspace
	    datapath.

   Common Columns:

     The overall purpose of these columns is described under Common  Columns  at
     the beginning of this document.

     external_ids: map of string-string pairs

SSL TABLE
     SSL configuration for an Open_vSwitch.

   Summary:
     private_key		   string
     certificate		   string
     ca_cert			   string
     bootstrap_ca_cert		   boolean
     Common Columns:
       external_ids		   map of string-string pairs

   Details:
     private_key: string
	    Name  of  a PEM file containing the private key used as the switch's
	    identity for SSL connections to the controller.

     certificate: string
	    Name of a PEM file containing a certificate, signed by the	certifi-
	    cate  authority (CA) used by the controller and manager, that certi-
	    fies the switch's private key, identifying a trustworthy switch.

     ca_cert: string
	    Name of a PEM file containing the CA certificate used to verify that
	    the switch is connected to a trustworthy controller.

     bootstrap_ca_cert: boolean
	    If set to true, then Open vSwitch will attempt to obtain the CA cer-
	    tificate from the controller on its first SSL connection and save it
	    to the named PEM file. If it is successful, it will immediately drop
	    the connection and reconnect, and from then on all	SSL  connections
	    must  be authenticated by a certificate signed by the CA certificate
	    thus  obtained.  This  option  exposes  the  SSL  connection  to   a
	    man-in-the-middle  attack  obtaining  the initial CA certificate. It
	    may still be useful for bootstrapping.

   Common Columns:

     The overall purpose of these columns is described under Common  Columns  at
     the beginning of this document.

     external_ids: map of string-string pairs

sFlow TABLE
     A	set  of  sFlow(R)  targets. sFlow is a protocol for remote monitoring of
     switches.

   Summary:
     agent			   optional string
     header			   optional integer
     polling			   optional integer
     sampling			   optional integer
     targets			   set of 1 or more strings
     Common Columns:
       external_ids		   map of string-string pairs

   Details:
     agent: optional string
	    Determines the agent address, that is, the IP  address  reported  to
	    collectors	as the source of the sFlow data. It may be an IP address
	    or the name of a network device. In the latter case, the network de-
	    vice's IP address is used,

	    If not specified, the agent device is figured from the first  target
	    address and the routing table. If the routing table does not contain
	    a  route  to  the target, the IP address defaults to the local_ip in
	    the collector's Controller.

	    If an agent IP address cannot be determined, sFlow is disabled.

     header: optional integer
	    Number of bytes of a sampled packet to send to the collector. If not
	    specified, the default is 128 bytes.

     polling: optional integer
	    Polling rate in seconds to send port statistics to the collector. If
	    not specified, defaults to 30 seconds.

     sampling: optional integer
	    Rate at which packets should be sampled and sent to  the  collector.
	    If	not specified, defaults to 400, which means one out of 400 pack-
	    ets, on average, will be sent to the collector.

     targets: set of 1 or more strings
	    sFlow targets in the form ip:port.

   Common Columns:

     The overall purpose of these columns is described under Common  Columns  at
     the beginning of this document.

     external_ids: map of string-string pairs

IPFIX TABLE
     Configuration for sending packets to IPFIX collectors.

     IPFIX is a protocol that exports a number of details about flows. The IPFIX
     implementation  in Open vSwitch samples packets at a configurable rate, ex-
     tracts flow information from those packets, optionally  caches  and  aggre-
     gates the flow information, and sends the result to one or more collectors.

     IPFIX in Open vSwitch can be configured two different ways:

	    *	   With  per-bridge  sampling,	Open vSwitch performs IPFIX sam-
		   pling automatically	on  all  packets  that	pass  through  a
		   bridge.  To	configure  per-bridge  sampling, create an IPFIX
		   record and point a Bridge table's ipfix  column  to	it.  The
		   Flow_Sample_Collector_Set  table  is  not used for per-bridge
		   sampling.

	    *	   With flow-based sampling, sample actions in the OpenFlow flow
		   table drive IPFIX sampling. See ovs-actions(7) for a descrip-
		   tion of the sample action.

		   Flow-based sampling	also  requires	database  configuration:
		   create  a IPFIX record that describes the IPFIX configuration
		   and a Flow_Sample_Collector_Set record  that  points  to  the
		   Bridge whose flow table holds the sample actions and to IPFIX
		   record.  The  ipfix in the Bridge table is not used for flow-
		   based sampling.

   Summary:
     targets			   set of strings
     cache_active_timeout	   optional integer, in range 0 to 4,200
     cache_max_flows		   optional integer, in range 0 to 4,294,967,295
     other_config : enable-tunnel-sampling
				   optional string, either true or false
     other_config : virtual_obs_id
				   optional string
     Per-Bridge Sampling:
       sampling 		   optional integer, in range 1 to 4,294,967,295
       obs_domain_id		   optional integer, in range 0 to 4,294,967,295
       obs_point_id		   optional integer, in range 0 to 4,294,967,295
       other_config : enable-input-sampling
				   optional string, either true or false
       other_config : enable-output-sampling
				   optional string, either true or false
     Common Columns:
       external_ids		   map of string-string pairs

   Details:
     targets: set of strings
	    IPFIX target collectors in the form ip:port.

     cache_active_timeout: optional integer, in range 0 to 4,200
	    The maximum period in seconds for which  an  IPFIX	flow  record  is
	    cached  and aggregated before being sent. If not specified, defaults
	    to 0. If 0, caching is disabled.

     cache_max_flows: optional integer, in range 0 to 4,294,967,295
	    The maximum number of IPFIX flow records that can  be  cached  at  a
	    time. If not specified, defaults to 0. If 0, caching is disabled.

     other_config : enable-tunnel-sampling: optional string, either true or
     false
	    Set  to true to enable sampling and reporting tunnel header 7-tuples
	    in IPFIX flow records. Tunnel sampling is enabled by default.

	    The following enterprise entities report the sampled tunnel info:

	    tunnelType:
		   ID: 891, and enterprise ID 6876 (VMware).

		   type: unsigned 8-bit integer.

		   data type semantics: identifier.

		   description: Identifier of the layer 2 network  overlay  net-
		   work  encapsulation	type:  0x01  VxLAN, 0x02 GRE, 0x03 LISP,
		   0x07 GENEVE.

	    tunnelKey:
		   ID: 892, and enterprise ID 6876 (VMware).

		   type: variable-length octetarray.

		   data type semantics: identifier.

		   description: Key which is used for identifying an  individual
		   traffic  flow  within  a  VxLAN  (24-bit VNI), GENEVE (24-bit
		   VNI), GRE (32-bit key), or LISP (24-bit instance ID)  tunnel.
		   The	key is encoded in this octetarray as a 3-, 4-, or 8-byte
		   integer ID in network byte order.

	    tunnelSourceIPv4Address:
		   ID: 893, and enterprise ID 6876 (VMware).

		   type: unsigned 32-bit integer.

		   data type semantics: identifier.

		   description: The IPv4 source address in the tunnel IP  packet
		   header.

	    tunnelDestinationIPv4Address:
		   ID: 894, and enterprise ID 6876 (VMware).

		   type: unsigned 32-bit integer.

		   data type semantics: identifier.

		   description:  The  IPv4  destination address in the tunnel IP
		   packet header.

	    tunnelProtocolIdentifier:
		   ID: 895, and enterprise ID 6876 (VMware).

		   type: unsigned 8-bit integer.

		   data type semantics: identifier.

		   description: The value of the protocol number in  the  tunnel
		   IP  packet  header. The protocol number identifies the tunnel
		   IP packet payload type.

	    tunnelSourceTransportPort:
		   ID: 896, and enterprise ID 6876 (VMware).

		   type: unsigned 16-bit integer.

		   data type semantics: identifier.

		   description: The source port identifier in the tunnel  trans-
		   port  header. For the transport protocols UDP, TCP, and SCTP,
		   this is the	source	port  number  given  in  the  respective
		   header.

	    tunnelDestinationTransportPort:
		   ID: 897, and enterprise ID 6876 (VMware).

		   type: unsigned 16-bit integer.

		   data type semantics: identifier.

		   description:  The  destination  port identifier in the tunnel
		   transport header. For the transport protocols UDP,  TCP,  and
		   SCTP,  this	is  the destination port number given in the re-
		   spective header.

	    Before Open vSwitch 2.5.90, other_config:enable-tunnel-sampling  was
	    only supported with per-bridge sampling, and ignored otherwise. Open
	    vSwitch 2.5.90 and later support other_config:enable-tunnel-sampling
	    for per-bridge and per-flow sampling.

     other_config : virtual_obs_id: optional string
	    A  string  that accompanies each IPFIX flow record. Its intended use
	    is for the ``virtual observation ID,'' an identifier  of  a  virtual
	    observation  point	that  is locally unique in a virtual network. It
	    describes a location in the virtual network where IP packets can  be
	    observed.  The  maximum  length  is 254 bytes. If not specified, the
	    field is omitted from the IPFIX flow record.

	    The following enterprise entity reports the specified virtual obser-
	    vation ID:

	    virtualObsID:
		   ID: 898, and enterprise ID 6876 (VMware).

		   type: variable-length string.

		   data type semantics: identifier.

		   description: A virtual observation domain ID that is  locally
		   unique in a virtual network.

	    This feature was introduced in Open vSwitch 2.5.90.

   Per-Bridge Sampling:

     These  values  affect only per-bridge sampling. See above for a description
     of the differences between per-bridge and flow-based sampling.

     sampling: optional integer, in range 1 to 4,294,967,295
	    The rate at which packets should be sampled and sent to each  target
	    collector. If not specified, defaults to 400, which means one out of
	    400 packets, on average, will be sent to each target collector.

     obs_domain_id: optional integer, in range 0 to 4,294,967,295
	    The  IPFIX	Observation  Domain ID sent in each IPFIX packet. If not
	    specified, defaults to 0.

     obs_point_id: optional integer, in range 0 to 4,294,967,295
	    The IPFIX Observation Point ID sent in each IPFIX  flow  record.  If
	    not specified, defaults to 0.

     other_config : enable-input-sampling: optional string, either true or false
	    By	default,  Open	vSwitch samples and reports flows at bridge port
	    input in IPFIX flow records. Set this column to false to disable in-
	    put sampling.

     other_config : enable-output-sampling: optional string, either true or
     false
	    By default, Open vSwitch samples and reports flows	at  bridge  port
	    output  in	IPFIX  flow records. Set this column to false to disable
	    output sampling.

   Common Columns:

     The overall purpose of these columns is described under Common  Columns  at
     the beginning of this document.

     external_ids: map of string-string pairs

Flow_Sample_Collector_Set TABLE
     A	set  of  IPFIX collectors of packet samples generated by OpenFlow sample
     actions. This table is used only for IPFIX  flow-based  sampling,	not  for
     per-bridge  sampling  (see  the  IPFIX  table  for a description of the two
     forms).

   Summary:
     id 			   integer, in range 0 to 4,294,967,295
     bridge			   Bridge
     ipfix			   optional IPFIX
     Common Columns:
       external_ids		   map of string-string pairs

   Details:
     id: integer, in range 0 to 4,294,967,295
	    The ID of this collector set, unique among	the  bridge's  collector
	    sets, to be used as the collector_set_id in OpenFlow sample actions.

     bridge: Bridge
	    The  bridge  into which OpenFlow sample actions can be added to send
	    packet samples to this set of IPFIX collectors.

     ipfix: optional IPFIX
	    Configuration of the set of IPFIX collectors to send one flow record
	    per sampled packet to.

   Common Columns:

     The overall purpose of these columns is described under Common  Columns  at
     the beginning of this document.

     external_ids: map of string-string pairs

AutoAttach TABLE
     Auto  Attach configuration within a bridge. The IETF Auto-Attach SPBM draft
     standard describes a compact method of using IEEE 802.1AB Link  Layer  Dis-
     covery  Protocol (LLDP) together with a IEEE 802.1aq Shortest Path Bridging
     (SPB) network to automatically attach network devices  to	individual  ser-
     vices  in	a  SPB network. The intent here is to allow network applications
     and devices using OVS to be able to easily take advantage of  features  of-
     fered by industry standard SPB networks.

     Auto Attach (AA) uses LLDP to communicate between a directly connected Auto
     Attach  Client (AAC) and Auto Attach Server (AAS). The LLDP protocol is ex-
     tended to add two new Type-Length-Value tuples (TLVs). The  first	new  TLV
     supports  the  ongoing  discovery	of directly connected AA correspondents.
     Auto Attach operates by regularly transmitting AA	discovery  TLVs  between
     the  AA  client and AA server. By exchanging these discovery messages, both
     the AAC and AAS learn the system name and system description of their peer.
     In the OVS context, OVS operates as the AA client and the AA server resides
     on a switch at the edge of the SPB network.

     Once AA discovery has been completed the AAC then uses the second	new  TLV
     to  deliver  identifier mappings from the AAC to the AAS. A primary feature
     of Auto Attach is to facilitate the mapping of VLANs  defined  outside  the
     SPB network onto service ids (ISIDs) defined within the SPM network. By do-
     ing  so  individual  external VLANs can be mapped onto specific SPB network
     services. These VLAN id to ISID mappings can be configured and managed  lo-
     cally using new options added to the ovs-vsctl command.

     The  Auto	Attach OVS feature does not provide a full implementation of the
     LLDP protocol. Support for the mandatory TLVs as defined by the LLDP  stan-
     dard  and support for the AA TLV extensions is provided. LLDP protocol sup-
     port in OVS can be enabled or disabled on a port by port basis.  LLDP  sup-
     port is disabled by default.

   Summary:
     system_name		   string
     system_description 	   string
     mappings			   map	of integer-integer pairs, key in range 0
				   to 16,777,215, value in range 0 to 4,095

   Details:
     system_name: string
	    The system_name string is  exported  in  LLDP  messages.  It  should
	    uniquely identify the bridge in the network.

     system_description: string
	    The  system_description  string  is  exported  in  LLDP messages. It
	    should describe the type of software and hardware.

     mappings: map of integer-integer pairs, key in range 0 to 16,777,215, value
     in range 0 to 4,095
	    A mapping from SPB network Individual Service Identifier  (ISID)  to
	    VLAN id.

Open vSwitch 2.17.12		 DB Schema 8.3.0	 ovs-vswitchd.conf.db(5)

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