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.\" ========================================================================
.\"
.IX Title "nbdkit 1"
.TH nbdkit 1 "2019-01-26" "nbdkit-1.10.3" "NBDKIT"
.\" For nroff, turn off justification.  Always turn off hyphenation; it makes
.\" way too many mistakes in technical documents.
.if n .ad l
.nh
.SH "NAME"
nbdkit \- toolkit for creating NBD servers
.SH "SYNOPSIS"
.IX Header "SYNOPSIS"
.Vb 10
\& nbdkit [\-D|\-\-debug PLUGIN|FILTER.FLAG=N]
\&        [\-e|\-\-exportname EXPORTNAME] [\-\-exit\-with\-parent]
\&        [\-\-filter FILTER ...] [\-f|\-\-foreground]
\&        [\-g|\-\-group GROUP] [\-i|\-\-ipaddr IPADDR]
\&        [\-\-log stderr|syslog]
\&        [\-n|\-\-newstyle] [\-o|\-\-oldstyle]
\&        [\-P|\-\-pidfile PIDFILE]
\&        [\-p|\-\-port PORT] [\-r|\-\-readonly]
\&        [\-\-run CMD] [\-s|\-\-single] [\-\-selinux\-label LABEL]
\&        [\-t|\-\-threads THREADS]
\&        [\-\-tls off|on|require]
\&        [\-\-tls\-certificates /path/to/certificates]
\&        [\-\-tls\-psk /path/to/pskfile] [\-\-tls\-verify\-peer]
\&        [\-U|\-\-unix SOCKET] [\-u|\-\-user USER]
\&        [\-v|\-\-verbose] [\-V|\-\-version]
\&        PLUGIN [KEY=VALUE [KEY=VALUE [...]]]
\& 
\& nbdkit \-\-dump\-config
\& 
\& nbdkit PLUGIN \-\-dump\-plugin
\& 
\& nbdkit \-\-help
.Ve
.SH "DESCRIPTION"
.IX Header "DESCRIPTION"
Network Block Device (\s-1NBD\s0) is a network protocol for accessing block
devices over the network.  Block devices are hard disks and things
that behave like hard disks such as disk images and virtual machines.
.PP
nbdkit is both a toolkit for creating \s-1NBD\s0 servers from
\&\*(L"unconventional\*(R" sources and the name of an \s-1NBD\s0 server.
.PP
nbdkit ships with many plugins and filters for performing common tasks
like serving files.  See the \*(L"\s-1EXAMPLES\*(R"\s0 and \*(L"\s-1SEE ALSO\*(R"\s0 sections
below, and look in the directory \f(CW\*(C`$libdir/nbdkit\*(C'\fR.
.PP
To create a new Network Block Device source, all you need to do is
write 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.
.PP
If you want to write an nbdkit plugin, you should read
\&\fBnbdkit\-plugin\fR\|(3).
.PP
You can give the full path to the plugin, like this:
.PP
.Vb 1
\& nbdkit $libdir/nbdkit/plugins/nbdkit\-file\-plugin.so [...]
.Ve
.PP
but it is usually more convenient to use this equivalent syntax:
.PP
.Vb 1
\& nbdkit file [...]
.Ve
.PP
\&\f(CW$libdir\fR is set at compile time.  To print it out, do:
.PP
.Vb 1
\& nbdkit \-\-dump\-config
.Ve
.SH "EXAMPLES"
.IX Header "EXAMPLES"
.SS "Basic file serving"
.IX Subsection "Basic file serving"
Serve file \fIdisk.img\fR on port 10809 using \fBnbdkit\-file\-plugin\fR\|(1),
and connect to it using \fBguestfish\fR\|(1):
.PP
.Vb 2
\& nbdkit file file=disk.img
\& guestfish \-\-rw \-\-format=raw \-a nbd://localhost
.Ve
.PP
Serve file \fIdisk.img\fR on port 10809, requiring clients to use
encrypted (\s-1TLS\s0) connections:
.PP
.Vb 1
\& nbdkit \-\-tls=require file file=disk.img
.Ve
.SS "Other nbdkit plugins"
.IX Subsection "Other nbdkit plugins"
Create a 1MB disk with one empty partition entirely on the command
line using \fBnbdkit\-data\-plugin\fR\|(1):
.PP
.Vb 4
\& nbdkit data data="@0x1b8 0xf8 0x21 0xdc 0xeb 0 0 0 0
\&                   2 0 0x83 0x20 0x20 0 1 0  0 0 0xff 0x7
\&                   @0x1fe 0x55 0xaa" \e
\&                   size=1M
.Ve
.PP
Forward an \s-1NBD\s0 connection over \s-1HTTP\s0 using \fBnbdkit\-curl\-plugin\fR\|(1):
.PP
.Vb 1
\& nbdkit \-r curl http://example.com/disk.img
.Ve
.SS "Combining plugins and filters"
.IX Subsection "Combining plugins and filters"
Serve only the first partition from compressed disk image
\&\fIdisk.img.xz\fR, combining \fBnbdkit\-xz\-plugin\fR\|(1) and
\&\fBnbdkit\-partition\-filter\fR\|(1):
.PP
.Vb 1
\& nbdkit \-\-filter=partition  xz disk.img.xz  partition=1
.Ve
.PP
To understand this command line:
.PP
.Vb 9
\&                     plugin name and plugin parameter
\&                                  │
\&                            ┌─────┴────┐
\&                            │          │
\& nbdkit \-\-filter=partition  xz disk.img.xz  partition=1
\&                  │                               │
\&                  └─────────────┬─────────────────┘
\&                                │
\&                filter name and filter parameter
.Ve
.PP
Create a scratch, empty nbdkit device and inject errors and delays,
for testing clients, using \fBnbdkit\-memory\-plugin\fR\|(1),
\&\fBnbdkit\-error\-filter\fR\|(1) and \fBnbdkit\-delay\-filter\fR\|(1):
.PP
.Vb 2
\& nbdkit \-\-filter=error \-\-filter=delay memory size=100M \e
\&        error\-rate=10% rdelay=1 wdelay=1
.Ve
.SS "Display information"
.IX Subsection "Display information"
Display information about nbdkit or a specific plugin:
.PP
.Vb 5
\& nbdkit \-\-help
\& nbdkit \-\-version
\& nbdkit \-\-dump\-config
\& nbdkit example1 \-\-help
\& nbdkit example1 \-\-dump\-plugin
.Ve
.SH "GLOBAL OPTIONS"
.IX Header "GLOBAL OPTIONS"
.IP "\fB\-\-help\fR" 4
.IX Item "--help"
Display brief command line usage information and exit.
.IP "\fB\-D\fR \s-1PLUGIN\s0.FLAG=N" 4
.IX Item "-D PLUGIN.FLAG=N"
.PD 0
.IP "\fB\-D\fR \s-1FILTER\s0.FLAG=N" 4
.IX Item "-D FILTER.FLAG=N"
.IP "\fB\-\-debug\fR \s-1PLUGIN\s0.FLAG=N" 4
.IX Item "--debug PLUGIN.FLAG=N"
.IP "\fB\-\-debug\fR \s-1FILTER\s0.FLAG=N" 4
.IX Item "--debug FILTER.FLAG=N"
.PD
Set the plugin or filter Debug Flag called \f(CW\*(C`FLAG\*(C'\fR to the integer
value \f(CW\*(C`N\*(C'\fR.  See \*(L"Debug Flags\*(R" in \fBnbdkit\-plugin\fR\|(3).
.IP "\fB\-\-dump\-config\fR" 4
.IX Item "--dump-config"
Dump out the compile-time configuration values and exit.
See \fBnbdkit\-probing\fR\|(1).
.IP "\fB\-\-dump\-plugin\fR" 4
.IX Item "--dump-plugin"
Dump out information about the plugin and exit.
See \fBnbdkit\-probing\fR\|(1).
.IP "\fB\-\-exit\-with\-parent\fR" 4
.IX Item "--exit-with-parent"
If the parent process exits, we exit.  This can be used to avoid
complicated cleanup or orphaned nbdkit processes.  There are some
important caveats with this, see \*(L"\s-1EXIT WITH PARENT\*(R"\s0 in \fBnbdkit\-captive\fR\|(1).
.Sp
An alternative to this is \*(L"\s-1CAPTIVE NBDKIT\*(R"\s0 in \fBnbdkit\-captive\fR\|(1).
.Sp
This option implies \fI\-\-foreground\fR.
.IP "\fB\-e\fR \s-1EXPORTNAME\s0" 4
.IX Item "-e EXPORTNAME"
.PD 0
.IP "\fB\-\-export\fR \s-1EXPORTNAME\s0" 4
.IX Item "--export EXPORTNAME"
.IP "\fB\-\-export\-name\fR \s-1EXPORTNAME\s0" 4
.IX Item "--export-name EXPORTNAME"
.IP "\fB\-\-exportname\fR \s-1EXPORTNAME\s0" 4
.IX Item "--exportname EXPORTNAME"
.PD
Set the exportname.
.Sp
If not set, exportname \f(CW""\fR (empty string) is used.  Exportnames are
not allowed with the oldstyle protocol.
.IP "\fB\-f\fR" 4
.IX Item "-f"
.PD 0
.IP "\fB\-\-foreground\fR" 4
.IX Item "--foreground"
.IP "\fB\-\-no\-fork\fR" 4
.IX Item "--no-fork"
.PD
\&\fIDon't\fR fork into the background.
.IP "\fB\-\-filter\fR \s-1FILTER\s0" 4
.IX Item "--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 \*(L"\s-1FILTERS\*(R"\s0 and
\&\fBnbdkit\-filter\fR\|(3).
.IP "\fB\-g\fR \s-1GROUP\s0" 4
.IX Item "-g GROUP"
.PD 0
.IP "\fB\-\-group\fR \s-1GROUP\s0" 4
.IX Item "--group GROUP"
.PD
Change group to \f(CW\*(C`GROUP\*(C'\fR after starting up.  A group name or numeric
group \s-1ID\s0 can be used.
.Sp
The server needs sufficient permissions to be able to do this.
Normally this would mean starting the server up as root.
.Sp
See also \fI\-u\fR.
.IP "\fB\-i\fR \s-1IPADDR\s0" 4
.IX Item "-i IPADDR"
.PD 0
.IP "\fB\-\-ip\-addr\fR \s-1IPADDR\s0" 4
.IX Item "--ip-addr IPADDR"
.IP "\fB\-\-ipaddr\fR \s-1IPADDR\s0" 4
.IX Item "--ipaddr IPADDR"
.PD
Listen on the specified interface.  The default is to listen on all
interfaces.  See also \fI\-p\fR.
.IP "\fB\-\-log=stderr\fR" 4
.IX Item "--log=stderr"
.PD 0
.IP "\fB\-\-log=syslog\fR" 4
.IX Item "--log=syslog"
.PD
Send error messages to either standard error (\fI\-\-log=stderr\fR) or to
the system log (\fI\-\-log=syslog\fR).
.Sp
The default is to send error messages to stderr, unless nbdkit
forks into the background in which case they are sent to syslog.
.Sp
For more details see \*(L"\s-1LOGGING\*(R"\s0 in \fBnbdkit\-service\fR\|(1).
.IP "\fB\-n\fR" 4
.IX Item "-n"
.PD 0
.IP "\fB\-\-new\-style\fR" 4
.IX Item "--new-style"
.IP "\fB\-\-newstyle\fR" 4
.IX Item "--newstyle"
.PD
Use the newstyle \s-1NBD\s0 protocol protocol.  This is the default in nbdkit
≥ 1.3.  In earlier versions the default was oldstyle.
See \fBnbdkit\-protocol\fR\|(1).
.IP "\fB\-o\fR" 4
.IX Item "-o"
.PD 0
.IP "\fB\-\-old\-style\fR" 4
.IX Item "--old-style"
.IP "\fB\-\-oldstyle\fR" 4
.IX Item "--oldstyle"
.PD
Use the oldstyle \s-1NBD\s0 protocol.  This \fIwas\fR the default in nbdkit
≤ 1.2, but now the default is newstyle.  Note this is incompatible
with newer features such as export names and \s-1TLS.\s0
See \fBnbdkit\-protocol\fR\|(1).
.IP "\fB\-P\fR \s-1PIDFILE\s0" 4
.IX Item "-P PIDFILE"
.PD 0
.IP "\fB\-\-pid\-file\fR \s-1PIDFILE\s0" 4
.IX Item "--pid-file PIDFILE"
.IP "\fB\-\-pidfile\fR \s-1PIDFILE\s0" 4
.IX Item "--pidfile PIDFILE"
.PD
Write \f(CW\*(C`PIDFILE\*(C'\fR (containing the process \s-1ID\s0 of the server) after
nbdkit becomes ready to accept connections.
.Sp
If the file already exists, it is overwritten.  nbdkit \fIdoes not\fR
delete the file when it exits.
.IP "\fB\-p\fR \s-1PORT\s0" 4
.IX Item "-p PORT"
.PD 0
.IP "\fB\-\-port\fR \s-1PORT\s0" 4
.IX Item "--port PORT"
.PD
Change the \s-1TCP/IP\s0 port number on which nbdkit serves requests.
The default is \f(CW10809\fR.  See also \fI\-i\fR.
.IP "\fB\-r\fR" 4
.IX Item "-r"
.PD 0
.IP "\fB\-\-read\-only\fR" 4
.IX Item "--read-only"
.IP "\fB\-\-readonly\fR" 4
.IX Item "--readonly"
.PD
The export will be read-only.  If a client writes, then it will get an
error.
.Sp
Note that some plugins inherently don't support writes.  With those
plugins the \fI\-r\fR option is added implicitly.
.Sp
\&\fBnbdkit\-cow\-filter\fR\|(1) can be placed over read-only plugins to
provide copy-on-write (or \*(L"snapshot\*(R") functionality.  If you are using
qemu as a client then it also supports snapshots.
.IP "\fB\-\-run\fR \s-1CMD\s0" 4
.IX Item "--run CMD"
Run nbdkit as a captive subprocess of \f(CW\*(C`CMD\*(C'\fR.  When \f(CW\*(C`CMD\*(C'\fR exits,
nbdkit is killed.  See \*(L"\s-1CAPTIVE NBDKIT\*(R"\s0 in \fBnbdkit\-captive\fR\|(1).
.Sp
This option implies \fI\-\-foreground\fR.
.IP "\fB\-s\fR" 4
.IX Item "-s"
.PD 0
.IP "\fB\-\-single\fR" 4
.IX Item "--single"
.IP "\fB\-\-stdin\fR" 4
.IX Item "--stdin"
.PD
Don't fork.  Handle a single \s-1NBD\s0 connection on stdin/stdout.  After
stdin closes, the server exits.
.Sp
You can use this option to run nbdkit from inetd or similar
superservers; 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
systemd, then it may be better to use
\&\*(L"\s-1SOCKET ACTIVATION\*(R"\s0 in \fBnbdkit\-service\fR\|(1) instead of this option.
.Sp
This option implies \fI\-\-foreground\fR.
.IP "\fB\-\-selinux\-label\fR SOCKET-LABEL" 4
.IX Item "--selinux-label SOCKET-LABEL"
Apply the SELinux label \f(CW\*(C`SOCKET\-LABEL\*(C'\fR to the nbdkit listening
socket.
.Sp
The common — perhaps only — use of this option is to allow libvirt
guests which are using SELinux and sVirt confinement to access nbdkit
Unix domain sockets:
.Sp
.Vb 1
\& nbdkit \-\-selinux\-label system_u:object_r:svirt_t:s0 ...
.Ve
.IP "\fB\-t\fR \s-1THREADS\s0" 4
.IX Item "-t THREADS"
.PD 0
.IP "\fB\-\-threads\fR \s-1THREADS\s0" 4
.IX Item "--threads THREADS"
.PD
Set the number of threads to be used per connection, which in turn
controls 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 prepared for out-of-order responses), set this to 1.
.IP "\fB\-\-tls=off\fR" 4
.IX Item "--tls=off"
.PD 0
.IP "\fB\-\-tls=on\fR" 4
.IX Item "--tls=on"
.IP "\fB\-\-tls=require\fR" 4
.IX Item "--tls=require"
.PD
Disable, enable or require \s-1TLS\s0 (authentication and encryption
support).  See \fBnbdkit\-tls\fR\|(1).
.IP "\fB\-\-tls\-certificates\fR /path/to/certificates" 4
.IX Item "--tls-certificates /path/to/certificates"
Set the path to the \s-1TLS\s0 certificates directory.  If not specified,
some built-in paths are checked.  See \fBnbdkit\-tls\fR\|(1) for more
details.
.IP "\fB\-\-tls\-psk\fR /path/to/pskfile" 4
.IX Item "--tls-psk /path/to/pskfile"
Set the path to the pre-shared keys (\s-1PSK\s0) file.  If used, this
overrides certificate authentication.  There is no built-in path.  See
\&\fBnbdkit\-tls\fR\|(1) for more details.
.IP "\fB\-\-tls\-verify\-peer\fR" 4
.IX Item "--tls-verify-peer"
Enables \s-1TLS\s0 client certificate verification.  The default is \fInot\fR to
check the client's certificate.
.IP "\fB\-U\fR \s-1SOCKET\s0" 4
.IX Item "-U SOCKET"
.PD 0
.IP "\fB\-\-unix\fR \s-1SOCKET\s0" 4
.IX Item "--unix SOCKET"
.IP "\fB\-U \-\fR" 4
.IX Item "-U -"
.IP "\fB\-\-unix \-\fR" 4
.IX Item "--unix -"
.PD
Accept connections on the Unix domain socket \f(CW\*(C`SOCKET\*(C'\fR (which is a
path).
.Sp
nbdkit creates this socket, but it will probably have incorrect
permissions (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.
.Sp
nbdkit does \fBnot\fR delete the socket file when it exits.  The caller
should delete the socket file after use (else if you try to start
nbdkit up again you will get an \f(CW\*(C`Address already in use\*(C'\fR error).
.Sp
If the socket name is \fI\-\fR then nbdkit generates a randomly named
private socket.  This is useful with \*(L"\s-1CAPTIVE NBDKIT\*(R"\s0 in \fBnbdkit\-captive\fR\|(1).
.IP "\fB\-u\fR \s-1USER\s0" 4
.IX Item "-u USER"
.PD 0
.IP "\fB\-\-user\fR \s-1USER\s0" 4
.IX Item "--user USER"
.PD
Change user to \f(CW\*(C`USER\*(C'\fR after starting up.  A user name or numeric user
\&\s-1ID\s0 can be used.
.Sp
The server needs sufficient permissions to be able to do this.
Normally this would mean starting the server up as root.
.Sp
See also \fI\-g\fR.
.IP "\fB\-v\fR" 4
.IX Item "-v"
.PD 0
.IP "\fB\-\-verbose\fR" 4
.IX Item "--verbose"
.PD
Enable verbose messages.
.Sp
It's a good idea to use \fI\-f\fR as well so the process does not fork
into the background (but not required).
.IP "\fB\-V\fR" 4
.IX Item "-V"
.PD 0
.IP "\fB\-\-version\fR" 4
.IX Item "--version"
.PD
Print the version number of nbdkit and exit.
.SH "PLUGIN CONFIGURATION"
.IX Header "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 \f(CW\*(C`key=value\*(C'\fR.  For example:
.PP
.Vb 1
\& nbdkit file file=disk.img
.Ve
.PP
To list all the options supported by a plugin, do:
.PP
.Vb 1
\& nbdkit \-\-help file
.Ve
.PP
To dump information about a plugin, do:
.PP
.Vb 1
\& nbdkit file \-\-dump\-plugin
.Ve
.SS "Magic script parameter"
.IX Subsection "Magic script parameter"
For some plugins, especially those supporting scripting languages like
Perl, if the first plugin argument does not contain an \f(CW\*(Aq=\*(Aq\fR
character then it is assumed to be \f(CW\*(C`script=value\*(C'\fR.
.PP
That allows scripting language plugins to do:
.PP
.Vb 1
\& nbdkit perl foo.pl [args...]
.Ve
.PP
which has the same meaning as:
.PP
.Vb 1
\& nbdkit perl script=foo.pl [args...]
.Ve
.SS "Shebang scripts"
.IX Subsection "Shebang scripts"
You can use \f(CW\*(C`#!\*(C'\fR to run nbdkit plugins written in most scripting
languages.  The file should be executable.  For example:
.PP
.Vb 4
\& #!/usr/sbin/nbdkit perl
\& sub open {
\&   # etc
\& }
.Ve
.PP
(see \fBnbdkit\-perl\-plugin\fR\|(3) for a full example).
.SH "FILTERS"
.IX Header "FILTERS"
One or more filters can be placed in front of an nbdkit plugin to
modify the behaviour of the plugin, using the \fI\-\-filter\fR parameter.
Filters can be used for example to limit requests to an offset/limit,
add copy-on-write support, or inject delays or errors (for testing).
.PP
.Vb 3
\&     NBD     ┌─────────┐    ┌─────────┐          ┌────────┐
\&  client ───▶│ filter1 │───▶│ filter2 │── ─ ─ ──▶│ plugin │
\& request     └─────────┘    └─────────┘          └────────┘
.Ve
.PP
Several existing filters are available in the \f(CW$filterdir\fR.  Use
\&\f(CW\*(C`nbdkit \-\-dump\-config\*(C'\fR to find the directory name.
.PP
How to write filters is described in \fBnbdkit\-filter\fR\|(3).
.SH "SIGNALS"
.IX Header "SIGNALS"
nbdkit responds to the following signals:
.ie n .IP """SIGINT""" 4
.el .IP "\f(CWSIGINT\fR" 4
.IX Item "SIGINT"
.PD 0
.ie n .IP """SIGQUIT""" 4
.el .IP "\f(CWSIGQUIT\fR" 4
.IX Item "SIGQUIT"
.ie n .IP """SIGTERM""" 4
.el .IP "\f(CWSIGTERM\fR" 4
.IX Item "SIGTERM"
.PD
The server exits cleanly.
.ie n .IP """SIGPIPE""" 4
.el .IP "\f(CWSIGPIPE\fR" 4
.IX Item "SIGPIPE"
This signal is ignored.
.SH "ENVIRONMENT VARIABLES"
.IX Header "ENVIRONMENT VARIABLES"
.ie n .IP """LISTEN_FDS""" 4
.el .IP "\f(CWLISTEN_FDS\fR" 4
.IX Item "LISTEN_FDS"
.PD 0
.ie n .IP """LISTEN_PID""" 4
.el .IP "\f(CWLISTEN_PID\fR" 4
.IX Item "LISTEN_PID"
.PD
If present in the environment when nbdkit starts up, these trigger
\&\*(L"\s-1SOCKET ACTIVATION\*(R"\s0 in \fBnbdkit\-service\fR\|(1).
.SH "SEE ALSO"
.IX Header "SEE ALSO"
.SS "Other topics"
.IX Subsection "Other topics"
\&\fBnbdkit\-captive\fR\|(1) — Run nbdkit under another process and have it
reliably cleaned up.
.PP
\&\fBnbdkit\-loop\fR\|(1) — Use nbdkit with the Linux kernel client to create
loop devices and loop mounts.
.PP
\&\fBnbdkit\-probing\fR\|(1) — How to probe for nbdkit configuration and plugins.
.PP
\&\fBnbdkit\-protocol\fR\|(1) — Which parts of the \s-1NBD\s0 protocol nbdkit supports.
.PP
\&\fBnbdkit\-service\fR\|(1) — Running nbdkit as a service, and systemd socket
activation.
.PP
\&\fBnbdkit\-tls\fR\|(1) — Authentication and encryption of \s-1NBD\s0 connections
(sometimes incorrectly called \*(L"\s-1SSL\*(R"\s0).
.SS "Plugins"
.IX Subsection "Plugins"
\&\fBnbdkit\-curl\-plugin\fR\|(1),
\&\fBnbdkit\-data\-plugin\fR\|(1),
\&\fBnbdkit\-example1\-plugin\fR\|(1),
\&\fBnbdkit\-example2\-plugin\fR\|(1),
\&\fBnbdkit\-example3\-plugin\fR\|(1),
\&\fBnbdkit\-example4\-plugin\fR\|(1),
\&\fBnbdkit\-ext2\-plugin\fR\|(1),
\&\fBnbdkit\-file\-plugin\fR\|(1),
\&\fBnbdkit\-floppy\-plugin\fR\|(1),
\&\fBnbdkit\-full\-plugin\fR\|(1),
\&\fBnbdkit\-guestfs\-plugin\fR\|(1),
\&\fBnbdkit\-gzip\-plugin\fR\|(1),
\&\fBnbdkit\-iso\-plugin\fR\|(1),
\&\fBnbdkit\-libvirt\-plugin\fR\|(1),
\&\fBnbdkit\-memory\-plugin\fR\|(1),
\&\fBnbdkit\-nbd\-plugin\fR\|(1),
\&\fBnbdkit\-null\-plugin\fR\|(1),
\&\fBnbdkit\-partitioning\-plugin\fR\|(1),
\&\fBnbdkit\-pattern\-plugin\fR\|(1),
\&\fBnbdkit\-random\-plugin\fR\|(1),
\&\fBnbdkit\-split\-plugin\fR\|(1),
\&\fBnbdkit\-streaming\-plugin\fR\|(1),
\&\fBnbdkit\-tar\-plugin\fR\|(1),
\&\fBnbdkit\-vddk\-plugin\fR\|(1),
\&\fBnbdkit\-xz\-plugin\fR\|(1),
\&\fBnbdkit\-zero\-plugin\fR\|(1)
;
\&\fBnbdkit\-lua\-plugin\fR\|(3),
\&\fBnbdkit\-ocaml\-plugin\fR\|(3),
\&\fBnbdkit\-perl\-plugin\fR\|(3),
\&\fBnbdkit\-python\-plugin\fR\|(3),
\&\fBnbdkit\-ruby\-plugin\fR\|(3),
\&\fBnbdkit\-sh\-plugin\fR\|(3),
\&\fBnbdkit\-tcl\-plugin\fR\|(3)
\&.
.SS "Filters"
.IX Subsection "Filters"
\&\fBnbdkit\-blocksize\-filter\fR\|(1),
\&\fBnbdkit\-cache\-filter\fR\|(1),
\&\fBnbdkit\-cow\-filter\fR\|(1),
\&\fBnbdkit\-delay\-filter\fR\|(1),
\&\fBnbdkit\-error\-filter\fR\|(1),
\&\fBnbdkit\-fua\-filter\fR\|(1),
\&\fBnbdkit\-log\-filter\fR\|(1),
\&\fBnbdkit\-nozero\-filter\fR\|(1),
\&\fBnbdkit\-offset\-filter\fR\|(1),
\&\fBnbdkit\-partition\-filter\fR\|(1),
\&\fBnbdkit\-truncate\-filter\fR\|(1),
\&\fBnbdkit\-xz\-filter\fR\|(1)
\&.
.SS "For developers"
.IX Subsection "For developers"
\&\fBnbdkit\-plugin\fR\|(3),
\&\fBnbdkit\-filter\fR\|(3).
.SS "Writing plugins in other programming languages"
.IX Subsection "Writing plugins in other programming languages"
\&\fBnbdkit\-lua\-plugin\fR\|(3),
\&\fBnbdkit\-ocaml\-plugin\fR\|(3),
\&\fBnbdkit\-perl\-plugin\fR\|(3),
\&\fBnbdkit\-python\-plugin\fR\|(3),
\&\fBnbdkit\-ruby\-plugin\fR\|(3),
\&\fBnbdkit\-sh\-plugin\fR\|(3),
\&\fBnbdkit\-tcl\-plugin\fR\|(3).
.SS "\s-1NBD\s0 clients"
.IX Subsection "NBD clients"
\&\fBqemu\fR\|(1),
\&\fBnbd\-client\fR\|(1),
\&\fBguestfish\fR\|(1).
.SS "nbdkit links"
.IX Subsection "nbdkit links"
http://github.com/libguestfs/nbdkit — Source code.
.SS "Other \s-1NBD\s0 servers"
.IX Subsection "Other NBD servers"
\&\fBqemu\-nbd\fR\|(1),
\&\fBnbd\-server\fR\|(1),
https://bitbucket.org/hirofuchi/xnbd.
.SS "Documentation for the \s-1NBD\s0 protocol"
.IX Subsection "Documentation for the NBD protocol"
https://github.com/NetworkBlockDevice/nbd/blob/master/doc/proto.md,
https://nbd.sourceforge.io/.
.SS "Similar protocols"
.IX Subsection "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.
.SS "Other manual pages of interest"
.IX Subsection "Other manual pages of interest"
\&\fBgnutls_priority_init\fR\|(3),
\&\fBqemu\-img\fR\|(1),
\&\fBpsktool\fR\|(1),
\&\fBsystemd.socket\fR\|(5).
.SH "AUTHORS"
.IX Header "AUTHORS"
Eric Blake
.PP
Richard W.M. Jones
.PP
Yann E. \s-1MORIN\s0
.PP
Nir Soffer
.PP
Pino Toscano
.SH "COPYRIGHT"
.IX Header "COPYRIGHT"
Copyright (C) 2013\-2018 Red Hat Inc.
.SH "LICENSE"
.IX Header "LICENSE"
Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions are
met:
.IP "\(bu" 4
Redistributions of source code must retain the above copyright
notice, this list of conditions and the following disclaimer.
.IP "\(bu" 4
Redistributions in binary form must reproduce the above copyright
notice, this list of conditions and the following disclaimer in the
documentation and/or other materials provided with the distribution.
.IP "\(bu" 4
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.
.PP
\&\s-1THIS SOFTWARE IS PROVIDED BY RED HAT AND CONTRIBUTORS\s0 ''\s-1AS IS\s0'' \s-1AND
ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL RED HAT OR
CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES\s0 (\s-1INCLUDING, BUT NOT
LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES\s0; \s-1LOSS OF
USE, DATA, OR PROFITS\s0; \s-1OR BUSINESS INTERRUPTION\s0) \s-1HOWEVER CAUSED AND
ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
OR TORT\s0 (\s-1INCLUDING NEGLIGENCE OR OTHERWISE\s0) \s-1ARISING IN ANY WAY OUT
OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
SUCH DAMAGE.\s0