DragonFly On-Line Manual Pages

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

       --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.

       -v, --verbose
	   Display extra debugging information

       -h, --help
	   Display this help and exit

       -V, --version
	   Display version information and exit

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.

				  2018-09-17			   QEMU-NBD(8)