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QEMU-NBD(8)							   QEMU-NBD(8)

NAME
       qemu-nbd	- QEMU Disk Network Block Device Server

SYNOPSIS
       qemu-nbd	[OPTION]... filename

       qemu-nbd	-d dev

DESCRIPTION
       Export a	QEMU disk image	using the NBD protocol.

OPTIONS
       filename	is a disk image	filename, or a set of block driver options if
       --image-opts is specified.

       dev is an NBD device.

       --object	type,id=id,...props...
	   Define a new	instance of the	type object class identified by	id.
	   See the qemu(1) manual page for full	details	of the properties
	   supported. The common object	types that it makes sense to define
	   are the "secret" object, which is used to supply passwords and/or
	   encryption keys, and	the "tls-creds"	object,	which is used to
	   supply TLS credentials for the qemu-nbd server.

       -p, --port=port
	   The TCP port	to listen on (default 10809)

       -o, --offset=offset
	   The offset into the image

       -b, --bind=iface
	   The interface to bind to (default 0.0.0.0)

       -k, --socket=path
	   Use a unix socket with path path

       --image-opts
	   Treat filename as a set of image options, instead of	a plain
	   filename. If	this flag is specified,	the -f flag should not be
	   used, instead the '"format="' option	should be set.

       -f, --format=fmt
	   Force the use of the	block driver for format	fmt instead of auto-
	   detecting

       -r, --read-only
	   Export the disk as read-only

       -P, --partition=num
	   Only	expose partition num

       -s, --snapshot
	   Use filename	as an external snapshot, create	a temporary file with
	   backing_file=filename, redirect the write to	the temporary one

       -l, --load-snapshot=snapshot_param
	   Load	an internal snapshot inside filename and export	it as an read-
	   only	device,	snapshot_param format is
	   'snapshot.id=[ID],snapshot.name=[NAME]' or '[ID_OR_NAME]'

       -n, --nocache
       --cache=cache
	   The cache mode to be	used with the file.  See the documentation of
	   the emulator's "-drive cache=..." option for	allowed	values.

       --aio=aio
	   Set the asynchronous	I/O mode between threads (the default) and
	   native (Linux only).

       --discard=discard
	   Control whether discard (also known as trim or unmap) requests are
	   ignored or passed to	the filesystem.	 discard is one	of ignore (or
	   off), unmap (or on).	 The default is	ignore.

       --detect-zeroes=detect-zeroes
	   Control the automatic conversion of plain zero writes by the	OS to
	   driver-specific optimized zero write	commands.  detect-zeroes is
	   one of off, on or unmap.  unmap converts a zero write to an unmap
	   operation and can only be used if discard is	set to unmap.  The
	   default is off.

       -c, --connect=dev
	   Connect filename to NBD device dev

       -d, --disconnect
	   Disconnect the device dev

       -e, --shared=num
	   Allow up to num clients to share the	device (default	1)

       -t, --persistent
	   Don't exit on the last connection

       -x, --export-name=name
	   Set the NBD volume export name. This	switches the server to use the
	   new style NBD protocol negotiation

       -D, --description=description
	   Set the NBD volume export description, as a human-readable string.
	   Requires the	use of -x

       --tls-creds=ID
	   Enable mandatory TLS	encryption for the server by setting the ID of
	   the TLS credentials object previously created with the --object
	   option.

       --fork
	   Fork	off the	server process and exit	the parent once	the server is
	   running.

       -v, --verbose
	   Display extra debugging information

       -h, --help
	   Display this	help and exit

       -V, --version
	   Display version information and exit

       -T, --trace [[enable=]pattern][,events=file][,file=file]
	   Specify tracing options.

	   [enable=]pattern
	       Immediately enable events matching pattern.  The	file must
	       contain one event name (as listed in the	trace-events-all file)
	       per line; globbing patterns are accepted	too.  This option is
	       only available if QEMU has been compiled	with the simple,
	       stderr or ftrace	tracing	backend.  To specify multiple events
	       or patterns, specify the	-trace option multiple times.

	       Use "-trace help" to print a list of names of trace points.

	   events=file
	       Immediately enable events listed	in file.  The file must
	       contain one event name (as listed in the	trace-events-all file)
	       per line; globbing patterns are accepted	too.  This option is
	       only available if QEMU has been compiled	with the simple,
	       stderr or ftrace	tracing	backend.

	   file=file
	       Log output traces to file.  This	option is only available if
	       QEMU has	been compiled with the simple tracing backend.

SEE ALSO
       qemu(1),	qemu-img(1)

AUTHOR
       Copyright (C) 2006 Anthony Liguori <anthony@codemonkey.ws>.  This is
       free software; see the source for copying conditions.  There is NO
       warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR
       PURPOSE.

				  2017-07-03			   QEMU-NBD(8)

NAME | SYNOPSIS | DESCRIPTION | OPTIONS | SEE ALSO | AUTHOR

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