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nbdkit(1)			     NBDKIT			       nbdkit(1)

NAME
     nbdkit - network block device (NBD) server

SYNOPSIS
      nbdkit [-4|--ipv4-only] [-6|--ipv6-only]
	     [-D|--debug PLUGIN|FILTER|nbdkit.FLAG=N]
	     [--exit-with-parent] [-e|--exportname EXPORTNAME]
	     [--filter=FILTER ...] [-f|--foreground]
	     [-g|--group GROUP] [-i|--ipaddr IPADDR] [--keepalive]
	     [--log=default|stderr|syslog|null|/path]
	     [--mask-handshake=MASK] [--name=NAME]
	     [-n|--newstyle] [--no-mc|--no-meta-contexts]
	     [--no-sr|--no-structured-replies] [-o|--oldstyle]
	     [-P|--pidfile PIDFILE] [-p|--port PORT] [--print-uri]
	     [-r|--readonly] [--run 'COMMAND ARGS ...']
	     [--selinux-label=LABEL] [-s|--single]
	     [--swap] [-t|--threads THREADS]
	     [--timeout=TIMEOUT] [--tls=off|on|require]
	     [--tls-certificates=/path/to/certificates]
	     [--tls-priority=PRIORITY]
	     [--tls-psk=/path/to/pskfile] [--tls-verify-peer]
	     [-U|--unix SOCKET|-] [-u|--user USER]
	     [-v|--verbose] [--vsock]
	     PLUGIN
	     [[KEY=]VALUE [KEY=VALUE [...]]] | @PATH

      nbdkit --dump-config

      nbdkit PLUGIN --dump-plugin

      nbdkit --help

      nbdkit [-V|--version]

      nbdkit [--short-options|--long-options]

DESCRIPTION
     Network Block Device (NBD) is a network protocol for accessing block de-
     vices over the network.  Block devices are hard disks and things that be-
     have like hard disks such as disk images and virtual machines.

     nbdkit is an NBD server, and also a powerful toolkit for creating your own
     NBD servers from aunconventionala sources.  nbdkit ships with many plugins
     for performing common tasks like serving local files.

   Plugins and filters
     nbdkit is different from other NBD servers because you can easily create
     new Network Block Device sources by writing a few glue functions, possibly
     in C, or perhaps in a high level language like Perl or Python.  The liberal
     licensing of nbdkit is meant to allow you to link nbdkit with proprietary
     libraries or to include nbdkit in proprietary code.

     If you want to write your own nbdkit plugin you should read nbdkit-plu-
     gin(3).

     nbdkit also has a concept of filters which can be layered on top of plug-
     ins.  Several filters are provided with nbdkit and if you want to write
     your own you should read nbdkit-filter(3).

EXAMPLES
   Basic file serving
     *	 Serve file disk.img on port 10809 using nbdkit-file-plugin(1), and con-
	 nect to it using guestfish(1):

	  nbdkit file disk.img
	  guestfish --rw --format=raw -a nbd://localhost

     *	 Serve file disk.img on port 10809, requiring clients to use encrypted
	 (TLS) connections:

	  nbdkit --tls=require file disk.img

   Other nbdkit plugins
     *	 Create a small disk containing test patterns using nbdkit-data-plu-
	 gin(1):

	  nbdkit data ' ( 0x55 0xAA )*2048 '

     *	 Forward an NBD connection to a remote server over HTTPS or SSH using
	 nbdkit-curl-plugin(1) or nbdkit-ssh-plugin(1):

	  nbdkit -r curl https://example.com/disk.img

	  nbdkit ssh host=example.com /var/tmp/disk.img

     *	 Create a sparse 1 terabyte RAM disk using nbdkit-memory-plugin(1) and
	 use it as a loop device (nbdkit-loop(1)):

	  nbdkit memory 1T
	  nbd-client localhost /dev/nbd0

     *	 Create a floppy disk image containing files from a local directory us-
	 ing nbdkit-floppy-plugin(1):

	  nbdkit floppy dir/

   Combining plugins and filters
     *	 Serve only the first partition from compressed disk image disk.img.xz,
	 combining nbdkit-partition-filter(1), nbdkit-xz-filter(1) and nbd-
	 kit-file-plugin(1).

	  nbdkit --filter=partition --filter=xz file disk.img.xz partition=1

	 To understand this command line:

				      plugin name and plugin parameter
							a
						aaaaaaaaa'aaaaaaa
						a	       a
	  nbdkit --filter=partition --filter=xz file disk.img.xz partition=1
			  a		 a			    a
			  aaaaaaaaaaaaaaaa'aaaaa~aaaaaaaaaaaaaaaaaaaaaa
					      a
				 filters and filter parameter

     *	 Create a scratch, empty nbdkit device and inject errors and delays, for
	 testing clients, using nbdkit-memory-plugin(1), nbdkit-error-filter(1)
	 and nbdkit-delay-filter(1):

	  nbdkit --filter=error --filter=delay memory 100M \
		 error-rate=10% rdelay=1 wdelay=1

   Writing plugins in shell script
     *	 Write a simple, custom plugin in shell script using nbdkit-sh-plu-
	 gin(3):

	  nbdkit sh - <<'EOF'
	    case "$1" in
	      get_size) echo 1M ;;
	      pread) dd if=/dev/zero count=$3 iflag=count_bytes ;;
	      *) exit 2 ;;
	    esac
	  EOF

     *	 The same example as above can be written entirely on the command line
	 using nbdkit-eval-plugin(1):

	  nbdkit eval get_size='echo 1M' \
		      pread='dd if=/dev/zero count=$3 iflag=count_bytes'

   Display information
     Display information about nbdkit or a specific plugin:

      nbdkit --help
      nbdkit --version
      nbdkit --dump-config
      nbdkit example1 --help
      nbdkit example1 --dump-plugin

   NBD URIs and endpoints
     NBD has a way to specify the URI of an NBD endpoint to make it easy to in-
     terconnect NBD tools.  Use the nbdkit --print-uri option to print the URI
     of this server instance.  For example:

      $ nbdkit -U /tmp/socket --print-uri null
      nbd+unix://?socket=/tmp/socket
      Shell-quoted URI: "nbd+unix://?socket=/tmp/socket"
      Command to query the NBD endpoint:
	nbdinfo "nbd+unix://?socket=/tmp/socket"

GLOBAL OPTIONS
     --help
	 Display brief command line usage information and exit.

     -4
     --ipv4-only
     -6
     --ipv6-only
	 When a non-numeric argument is passed to the -i option (such as a Fully
	 Qualified Domain Name, or a host name from "/etc/hosts"), restrict the
	 name resolution to IPv4 or IPv6 addresses.

	 When the -i option is omitted, listen on only the IPv4 or IPv6 address
	 of all interfaces (0.0.0.0 or "::", respectively).

	 When both -4 and -6 options are present on the command line, the last
	 one takes effect.

     -D PLUGIN.FLAG=N
     -D FILTER.FLAG=N
     --debug PLUGIN.FLAG=N
     --debug FILTER.FLAG=N
	 Set the plugin or filter Debug Flag called "FLAG" to the integer value
	 "N".  See "Debug Flags" in nbdkit-plugin(3).

     -D nbdkit.FLAG=N
     --debug nbdkit.FLAG=N
	 (nbdkit aY 1.18)

	 Set the nbdkit server Debug Flag called "FLAG" to the integer value
	 "N".  See "SERVER DEBUG FLAGS" below.

     --dump-config
	 Dump out the compile-time configuration values and exit.  See nbd-
	 kit-probing(1).

     --dump-plugin
	 Dump out information about the plugin and exit.  See nbdkit-probing(1).

     --exit-with-parent
	 If the parent process exits, we exit.	This can be used to avoid com-
	 plicated cleanup or orphaned nbdkit processes.  There are some impor-
	 tant caveats with this, see "EXIT WITH PARENT" in nbdkit-captive(1).

	 An alternative to this is "CAPTIVE NBDKIT" in nbdkit-captive(1).

	 This option implies --foreground.

     -e EXPORTNAME
     --export=EXPORTNAME
     --export-name=EXPORTNAME
     --exportname=EXPORTNAME
	 Set a preferred exportname to expose in the shell environment created
	 during --run.	The use of this option without --run has no effect.
	 This option does not change what nbdkit advertises as a server, but can
	 aid in writing a captive client that wants to access particular content
	 from a plugin that differentiates content based on the client's choice
	 of export name.

	 If not set, the --run environment is set to access the default export-
	 name "" (empty string).

     --filter=FILTER
	 Add a filter before the plugin.  This option may be given one or more
	 times to stack filters in front of the plugin.  They are processed in
	 the order they appear on the command line.  See "FILTERS" and nbd-
	 kit-filter(3).

     -f
     --foreground
     --no-fork
	 Don't fork into the background.

     -g GROUP
     --group=GROUP
	 Change group to "GROUP" after starting up.  A group name or numeric
	 group ID can be used.

	 The server needs sufficient permissions to be able to do this.  Nor-
	 mally this would mean starting the server up as root.

	 See also -u.

     -i IPADDR
     --ip-addr=IPADDR
     --ipaddr=IPADDR
	 Listen on the specified interface.  The default is to listen on all in-
	 terfaces.  See also -4, -6, and -p.

     --keep-alive
     --keepalive
	 Enable TCP keepalive ("SO_KEEPALIVE") on TCP sockets.	This can allow
	 clients that reboot to be detected earlier.  You may also have to ad-
	 just kernel parameters.  For Linux see:
	 https://tldp.org/HOWTO/TCP-Keepalive-HOWTO/usingkeepalive.html

	 Only has an effect if nbdkit uses a TCP socket (so not for -U, -s,
	 etc.)

     --log=stderr
     --log=syslog
     --log=null
     --log=/path
     --log=default
	 Send error messages to standard error (--log=stderr), or to the system
	 log (--log=syslog), discard them completely (--log=null, not recom-
	 mended for normal use), or append them to a file (which must be an ab-
	 solute path).

	 The default (if --log is not used, or if you use --log=default) is:
	 send error messages to stderr, unless nbdkit forks into the background
	 in which case they are sent to syslog.

	 These messages can be generated from plugins by calling nbdkit_error(3)
	 or nbdkit_verror(3).

	 Debug messages (-v/--verbose) always go to standard error and are never
	 sent to the system log.

     --long-options
	 List the long command line options (those starting with --) supported
	 by this build of nbdkit.  The options are listed one per line, and then
	 nbdkit exits.	This is used mainly to implement tab completion.  See
	 also --short-options.

     --mask-handshake=MASK
	 This option can be used to mask off particular global features which
	 are advertised during new-style handshake (defaulting to all supported
	 bits set).  See nbdkit-protocol(1).

     --name=NAME
	 Name this nbdkit instance.  This allows you to associate names with
	 nbdkit processes, if you have several.  The name appears in error and
	 debug messages, but is otherwise unused by nbdkit.  The name can be any
	 string, but usually a short string containing only letters, numbers and
	 common punctuation is best.

     -n
     --new-style
     --newstyle
	 Use the newstyle NBD protocol.  This is the default in nbdkit aY 1.3.
	 In earlier versions the default was oldstyle.	See nbdkit-protocol(1).

     --no-mc
     --no-meta-contexts
	 Do not advertise meta contexts.  Normally, nbdkit handles all client
	 requests for arbitrary meta context names, with the response being af-
	 firmative for only the "base:allocation" meta context (nbdkit synthe-
	 sizes this context even when the plugin does not support extents), so
	 that clients can use the block status command.  However, meta contexts
	 are not a mandatory part of the newstyle NBD protocol, so this option
	 can be used to debug client fallbacks for dealing with older servers
	 that lack meta context support.  See nbdkit-protocol(1).

     --no-sr
     --no-structured-replies
	 Do not advertise structured replies.  A client must request structured
	 replies to take advantage of block status and potential sparse reads;
	 however, as structured reads are not a mandatory part of the newstyle
	 NBD protocol, this option can be used to debug client fallbacks for
	 dealing with older servers.  See nbdkit-protocol(1).

     -o
     --old-style
     --oldstyle
	 Use the oldstyle NBD protocol.  This was the default in nbdkit ax 1.2,
	 but now the default is newstyle.  Note this is incompatible with newer
	 features such as export names and TLS.  See nbdkit-protocol(1).

     -P PIDFILE
     --pid-file=PIDFILE
     --pidfile=PIDFILE
	 Write "PIDFILE" (containing the process ID of the server) after nbdkit
	 becomes ready to accept connections.

	 If the file already exists, it is overwritten.  nbdkit does not delete
	 the file when it exits.

     -p PORT
     --port=PORT
	 Change the TCP/IP port number on which nbdkit serves requests.  The de-
	 fault is 10809.  See also -i.

     --print-uri
	 Print the URI.  See "NBD URIs and endpoints" above.

     -r
     --read-only
     --readonly
	 The export will be read-only.	If a client writes, then it will get an
	 error.

	 Note that some plugins inherently don't support writes.  With those
	 plugins the -r option is added implicitly.

	 nbdkit-cow-filter(1) can be placed over read-only plugins to provide
	 copy-on-write (or "snapshot") functionality.  If you are using qemu as
	 a client then it also supports snapshots.  nbdkit-readonly-filter(1) or
	 nbdkit-protect-filter(1) can selectively add write-protection.

     --run 'COMMAND ARGS ...'
	 Run nbdkit as a captive subprocess of the command.  When the command
	 exits, nbdkit is killed.  See "CAPTIVE NBDKIT" in nbdkit-captive(1).

	 Note that the command is executed by /bin/sh.	On some platforms like
	 Debian this might not be a full-featured shell.

	 This option implies --foreground.

	 In nbdkit ax 1.34 you normally had to add -U -, otherwise nbdkit would
	 use a TCP/IP port which was not what you wanted.  In nbdkit aY 1.36,
	 using --run implies -U -.  If you want the old behaviour of nbdkit then
	 you must use the --port option explicitly.

     --selinux-label=SOCKET-LABEL
	 Apply the SELinux label "SOCKET-LABEL" to the nbdkit listening socket.

	 The common a perhaps only a use of this option is to allow libvirt
	 guests which are using SELinux and sVirt confinement to access nbdkit
	 Unix domain sockets.  The example below shows how to do this.	Note
	 that the socket and filesystem labels are different.

	  nbdkit -U /tmp/sock --selinux-label=system_u:object_r:svirt_socket_t:s0 ...
	  chcon system_u:object_r:svirt_image_t:s0 /tmp/sock

     --short-options
	 List the short command line options (single letter options starting
	 with -) supported by this build of nbdkit.  The options are listed one
	 per line, and then nbdkit exits.  This is used mainly to implement tab
	 completion.  See also --long-options.

     -s
     --single
     --stdin
	 Don't fork.  Handle a single NBD connection on stdin/stdout.  After
	 stdin closes, the server exits.

	 You can use this option to run nbdkit from inetd or similar super-
	 servers; or just for testing; or if you want to run nbdkit in a
	 non-conventional way.	Note that if you want to run nbdkit from sys-
	 temd, then it may be better to use "SOCKET ACTIVATION" in nbdkit-ser-
	 vice(1) instead of this option.

	 This option implies --foreground.

     --swap
	 (nbdkit aY 1.18)

	 Specifies that the NBD device will be used as swap space loop mounted
	 on the same machine which is running nbdkit.  To avoid deadlocks this
	 locks the whole nbdkit process into memory using mlockall(2).	This may
	 require additional permissions, such as starting the server as root or
	 raising the "RLIMIT_MEMLOCK" (ulimit(1) -l) limit on the process.

     -t THREADS
     --threads=THREADS
	 Set the number of threads to be used per connection, which in turn con-
	 trols the number of outstanding requests that can be processed at once.
	 Only matters for plugins with thread_model=parallel (where it defaults
	 to 16).  To force serialized behavior (useful if the client is not pre-
	 pared for out-of-order responses), set this to 1.

     --timeout=TIMEOUT
	 (nbdkit aY 1.42, not Windows)

	 If the client does not negotiate a full NBD session within "TIMEOUT"
	 seconds, then drop the connection.  This can be used as an additional
	 security measure to ensure that clients don't consume resources by
	 opening lots of connections and then not negotiating (or negotiating
	 slowly) the full NBD session.	It is particularly useful in conjunction
	 with TLS client authentication (see nbdkit-tls(1)).

	 The timeout is measured from the point of the initial TCP connection to
	 the point where NBD session negotiation ends (including TLS, if used).
	 If the timeout is exceeded during this negotiation, the connection is
	 dropped.  Setting this too low will cause problems for clients listing
	 lots of exports.

	 The default is no timeout.

	 "TIMEOUT" can be any format supported by nbdkit_parse_delay(3).

     --tls=off
     --tls=on
     --tls=require
	 Disable, enable or require TLS (authentication and encryption support).
	 See nbdkit-tls(1).

     --tls-certificates=/path/to/certificates
	 Set the path to the TLS certificates directory.  If not specified, some
	 built-in paths are checked.  See nbdkit-tls(1) for more details.

     --tls-priority=PRIORITY
	 Override the TLS priority string.  The TLS priority controls which ci-
	 phers, key exchange methods and MACs are used and in what order.  See
	 "Priority strings" in the GnuTLS manual

	 The default may be set when nbdkit is built (and if not set, defaults
	 to "NORMAL").

     --tls-psk=/path/to/pskfile
	 Set the path to the pre-shared keys (PSK) file.  If used, this over-
	 rides certificate authentication.  There is no built-in path.	See nbd-
	 kit-tls(1) for more details.

     --tls-verify-peer
	 Enables TLS client certificate verification.  The default is not to
	 check the client's certificate.

     -U SOCKET
     --unix=SOCKET
     -U -
     --unix -
	 Accept connections on the Unix domain socket "SOCKET" (which is a
	 path).

	 nbdkit creates this socket, but it will probably have incorrect permis-
	 sions (too permissive).  If it is a problem that some unauthorized user
	 could connect to this socket between the time that nbdkit starts up and
	 the authorized user connects, then put the socket into a directory that
	 has restrictive permissions.

	 nbdkit does not delete the socket file when it exits.	The caller
	 should delete the socket file after use (else if you try to start nbd-
	 kit up again you will get an "Address already in use" error).

	 If the socket name is - then nbdkit generates a randomly named private
	 socket.  This is implied by the --run option.	See also "CAPTIVE NBD-
	 KIT" in nbdkit-captive(1).

     -u USER
     --user=USER
	 Change user to "USER" after starting up.  A user name or numeric user
	 ID can be used.

	 The server needs sufficient permissions to be able to do this.  Nor-
	 mally this would mean starting the server up as root.

	 See also -g.

     -v
     --verbose
	 Enable verbose messages.

	 It's a good idea to use -f as well so the process does not fork into
	 the background.  The messages are sent to stderr.  Note they are not
	 affected by the --log option (which is only for error messages).

	 These messages can be generated from plugins by calling nbdkit_debug(3)
	 or nbdkit_vdebug(3).

     -V
     --version
	 Print the version number of nbdkit and exit.

	 The --dump-config option provides separate major and minor numbers and
	 may be easier to parse from shell scripts.

     --vsock
	 (nbdkit aY 1.16)

	 Use the AF_VSOCK protocol (instead of TCP/IP).  You must use this in
	 conjunction with -p/--port.  See "AF_VSOCK" in nbdkit-service(1).

PLUGIN NAME
     You can give the full path to the plugin, like this:

      nbdkit $libdir/nbdkit/plugins/nbdkit-file-plugin.so [...]

     but it is usually more convenient to use this equivalent syntax:

      nbdkit file [...]

     $libdir is set at compile time.  To print it out, do:

      nbdkit --dump-config

PLUGIN CONFIGURATION
     After specifying the plugin name you can (optionally, it depends on the
     plugin) give plugin configuration on the command line in the form of
     "key=value".  For example:

      nbdkit file file=disk.img

     To list all the options supported by a plugin, do:

      nbdkit --help file

     To dump information about a plugin, do:

      nbdkit file --dump-plugin

   Magic parameters
     Some plugins declare a special "magic config key".  This is a key which is
     assumed if no "key=" part is present.  For example:

      nbdkit file disk.img

     is assumed to be "file=disk.img" because the file plugin declares "file" as
     its magic config key.  There can be ambiguity in the parsing of magic con-
     fig keys if the value might look like a "key=value".  If there could be am-
     biguity then modify the value, eg. by prefixing it with "./"

     There is also a special exception for plugins which do not declare a magic
     config key, but where the first plugin argument does not contain an '='
     character: it is assumed to be "script=value".  This is used by scripting
     language plugins:

      nbdkit perl foo.pl [args...]

     has the same meaning as:

      nbdkit perl script=foo.pl [args...]

   @PATH
     If you need to pass a large number of key=value parameters, you can place
     them in an external file, for example:

      $ cat partitions.txt
      # The list of partitions to load:
      file=partition1.img
      file=partition2.img
      file=partition3.img
      $ nbdkit partitioning @./partitions.txt

     The pathname after the "@" must contain at least one "/" character (this is
     to avoid compatibility problems with some existing plugins), so if the file
     is the current directory as in the example above, use "@./filename"

     There must be one parameter per line.  Lines beginning with "#" and blank
     lines are ignored.

     This only works for "key=value" plugin & filter parameters (not for the
     plugin name or --options).  You can use multiple @PATH parameters.

     You or use @PATH recursively in another @PATH file.  The path in that case
     is taken relative to the containing file.

   Shebang scripts
     You can use "#!" to run nbdkit plugins written in most scripting languages.
     The file should be executable.  For example:

      #!/usr/sbin/nbdkit perl
      sub open {
	# etc
      }

     (see nbdkit-perl-plugin(3) for a full example).

SERVER DEBUG FLAGS
     As well as enabling or disabling debugging in the server using --verbose
     you can control extra debugging in the server using the -D nbdkit.* flags
     listed in this section.  Note these flags are an internal implementation
     detail of the server and may be changed or removed at any time in the fu-
     ture.

     -D nbdkit.backend.controlpath=0
     -D nbdkit.backend.controlpath=1
     -D nbdkit.backend.datapath=0
     -D nbdkit.backend.datapath=1
	 These flags control the verbosity of nbdkit backend debugging messages
	 (the ones which show every request processed by the server).  The de-
	 fault for both settings is 1 (normal debugging) but you can set them to
	 0 to suppress these messages.

	 -D nbdkit.backend.datapath=0 is the more useful setting which lets you
	 suppress messages about pread, pwrite, zero, trim, etc. commands.  When
	 transferring large amounts of data these messages are numerous and not
	 usually very interesting.

	 -D nbdkit.backend.controlpath=0 suppresses the non-datapath commands
	 (config, open, close, can_write, etc.)

     -D nbdkit.environ=1
	 Print nbdkit's environment variables in the debug output at start up.
	 This is insecure because environment variables may contain both sensi-
	 tive and user-controlled information, so it should not be used rou-
	 tinely.  But it is useful for tracking down problems related to envi-
	 ronment variables.

     -D nbdkit.tls.log=N
	 Enable TLS logging.  "N" can be in the range 0 (no logging) to 99.  See
	 gnutls_global_set_log_level(3).

     -D nbdkit.tls.session=1
	 Print additional information about the TLS session, such as the type of
	 authentication and encryption, and client certificate information.

SIGNALS
     nbdkit responds to the following signals:

     "SIGINT"
     "SIGQUIT"
     "SIGTERM"
	 The server exits cleanly.

     "SIGPIPE"
	 This signal is ignored.

ENVIRONMENT VARIABLES
     "LISTEN_FDS"
     "LISTEN_PID"
	 If present in the environment when nbdkit starts up, these trigger
	 "SOCKET ACTIVATION" in nbdkit-service(1).

SEE ALSO
   Other topics
     nbdkit-captive(1) a Run nbdkit under another process and have it reliably
     cleaned up.

     nbdkit-client(1) a How to mount NBD filesystems on a client machine.

     nbdkit-loop(1) a Use nbdkit with the Linux kernel client to create loop de-
     vices and loop mounts.

     nbdkit-probing(1) a How to probe for nbdkit configuration and plugins.

     nbdkit-protocol(1) a Which parts of the NBD protocol nbdkit supports.

     nbdkit-security(1) a Lists past security issues in nbdkit.

     nbdkit-service(1) a Running nbdkit as a service, and systemd socket activa-
     tion.

     nbdkit-tls(1) a Authentication and encryption of NBD connections (sometimes
     incorrectly called "SSL").

     nbdkit-tracing(3) a Adding user statically defined tracing (USDT) probes to
     nbdkit.

   Plugins
     nbdkit-blkio-plugin(1), nbdkit-cdi-plugin(1), nbdkit-curl-plugin(1), nbd-
     kit-data-plugin(1), nbdkit-eval-plugin(1), nbdkit-example1-plugin(1), nbd-
     kit-example2-plugin(1), nbdkit-example3-plugin(1), nbdkit-example4-plu-
     gin(1), nbdkit-file-plugin(1), nbdkit-floppy-plugin(1), nbdkit-full-plu-
     gin(1), nbdkit-gcs-plugin(1), nbdkit-guestfs-plugin(1), nbdkit-info-plu-
     gin(1), nbdkit-iso-plugin(1), nbdkit-libvirt-plugin(1), nbdkit-lin-
     uxdisk-plugin(1), nbdkit-memory-plugin(1), nbdkit-nbd-plugin(1), nbd-
     kit-nfs-plugin(1), nbdkit-null-plugin(1), nbdkit-ondemand-plugin(1), nbd-
     kit-ones-plugin(1), nbdkit-partitioning-plugin(1), nbdkit-pattern-plu-
     gin(1), nbdkit-random-plugin(1), nbdkit-S3-plugin(1), nbdkit-sparse-ran-
     dom-plugin(1), nbdkit-split-plugin(1), nbdkit-ssh-plugin(1), nbdkit-tm-
     pdisk-plugin(1), nbdkit-torrent-plugin(1), nbdkit-vddk-plugin(1), nbd-
     kit-vram-plugin(1), nbdkit-zero-plugin(1) ; nbdkit-cc-plugin(3), nbd-
     kit-golang-plugin(3), nbdkit-lua-plugin(3), nbdkit-ocaml-plugin(3), nbd-
     kit-perl-plugin(3), nbdkit-python-plugin(3), nbdkit-rust-plugin(3), nbd-
     kit-sh-plugin(3), nbdkit-tcl-plugin(3) .

   Filters
     nbdkit-blocksize-filter(1), nbdkit-blocksize-policy-filter(1), nbd-
     kit-bzip2-filter(1), nbdkit-cache-filter(1), nbdkit-checkwrite-filter(1),
     nbdkit-count-filter(1), nbdkit-cow-filter(1), nbdkit-ddrescue-filter(1),
     nbdkit-delay-filter(1), nbdkit-error-filter(1), nbdkit-evil-filter(1), nbd-
     kit-exitlast-filter(1), nbdkit-exitwhen-filter(1), nbdkit-exportname-fil-
     ter(1), nbdkit-ext2-filter(1), nbdkit-extentlist-filter(1), nbdkit-fua-fil-
     ter(1), nbdkit-gzip-filter(1), nbdkit-indexed-gzip-filter(1), nbd-
     kit-ip-filter(1), nbdkit-limit-filter(1), nbdkit-log-filter(1), nbd-
     kit-luks-filter(1), nbdkit-lzip-filter(1), nbdkit-map-filter(1), nbd-
     kit-multi-conn-filter(1), nbdkit-nocache-filter(1), nbdkit-noextents-fil-
     ter(1), nbdkit-nofilter-filter(1), nbdkit-noparallel-filter(1), nbd-
     kit-nozero-filter(1), nbdkit-offset-filter(1), nbdkit-openonce-filter(1),
     nbdkit-partition-filter(1), nbdkit-pause-filter(1), nbdkit-protect-fil-
     ter(1), nbdkit-qcow2dec-filter(1), nbdkit-rate-filter(1), nbdkit-reada-
     head-filter(1), nbdkit-readonly-filter(1), nbdkit-retry-filter(1), nbd-
     kit-retry-request-filter(1), nbdkit-rotational-filter(1), nbdkit-scan-fil-
     ter(1), nbdkit-spinning-filter(1), nbdkit-stats-filter(1), nbdkit-swab-fil-
     ter(1), nbdkit-tar-filter(1), nbdkit-time-limit-filter(1), nbdkit-tls-fall-
     back-filter(1), nbdkit-truncate-filter(1), nbdkit-xz-filter(1) .

   For developers
     nbdkit-plugin(3), nbdkit-filter(3).

   Writing plugins in other programming languages
     nbdkit-cc-plugin(3), nbdkit-golang-plugin(3), nbdkit-lua-plugin(3), nbd-
     kit-ocaml-plugin(3), nbdkit-perl-plugin(3), nbdkit-python-plugin(3), nbd-
     kit-rust-plugin(3), nbdkit-sh-plugin(3), nbdkit-tcl-plugin(3) .

   Release notes for previous releases of nbdkit
     nbdkit-release-notes-1.46(1), nbdkit-release-notes-1.44(1), nbdkit-re-
     lease-notes-1.42(1), nbdkit-release-notes-1.40(1), nbdkit-re-
     lease-notes-1.38(1), nbdkit-release-notes-1.36(1), nbdkit-re-
     lease-notes-1.34(1), nbdkit-release-notes-1.32(1), nbdkit-re-
     lease-notes-1.30(1), nbdkit-release-notes-1.28(1), nbdkit-re-
     lease-notes-1.26(1), nbdkit-release-notes-1.24(1), nbdkit-re-
     lease-notes-1.22(1), nbdkit-release-notes-1.20(1), nbdkit-re-
     lease-notes-1.18(1), nbdkit-release-notes-1.16(1), nbdkit-re-
     lease-notes-1.14(1), nbdkit-release-notes-1.12(1), nbdkit-re-
     lease-notes-1.10(1), nbdkit-release-notes-1.8(1), nbdkit-re-
     lease-notes-1.6(1), nbdkit-release-notes-1.4(1).

   NBD clients
     guestfish(1), libnbd(3), nbd-client(1), nbdcopy(1), nbdfuse(1), nbdinfo(1),
     nbdsh(1), qemu(1).

   nbdkit links
     http://gitlab.com/nbdkit/nbdkit a Source code.

   Other NBD servers
     qemu-nbd(1), nbd-server(1), https://github.com/bignaux/lwNBD, https://bit-
     bucket.org/hirofuchi/xnbd.

   Documentation for the NBD protocol
     https://github.com/NetworkBlockDevice/nbd/blob/master/doc/proto.md,
     https://github.com/NetworkBlockDevice/nbd/blob/master/doc/uri.md,
     https://nbd.sourceforge.io/.

   Similar protocols
     https://en.wikipedia.org/wiki/iSCSI,
     https://en.wikipedia.org/wiki/ATA_over_Ethernet,
     https://en.wikipedia.org/wiki/Fibre_Channel_over_Ethernet.

   Other manual pages of interest
     gnutls_priority_init(3), qemu-img(1), psktool(1), systemd.socket(5).

AUTHORS
     Eric Blake

     Laszlo Ersek

     Richard W.M. Jones

     Yann E. MORIN

     Nikolaus Rath

     FranA<section>ois Revol

     Nir Soffer

     Alan Somers

     Pino Toscano

COPYRIGHT
     Copyright Red Hat

LICENSE
     Redistribution and use in source and binary forms, with or without modifi-
     cation, are permitted provided that the following conditions are met:

     *	 Redistributions of source code must retain the above copyright notice,
	 this list of conditions and the following disclaimer.

     *	 Redistributions in binary form must reproduce the above copyright no-
	 tice, this list of conditions and the following disclaimer in the docu-
	 mentation and/or other materials provided with the distribution.

     *	 Neither the name of Red Hat nor the names of its contributors may be
	 used to endorse or promote products derived from this software without
	 specific prior written permission.

     THIS SOFTWARE IS PROVIDED BY RED HAT AND CONTRIBUTORS ''AS IS'' AND ANY EX-
     PRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
     WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DIS-
     CLAIMED. IN NO EVENT SHALL RED HAT OR CONTRIBUTORS BE LIABLE FOR ANY DI-
     RECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
     (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SER-
     VICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
     CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABIL-
     ITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
     THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAM-
     AGE.

nbdkit-1.46.2			   2026-08-30			       nbdkit(1)

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