Provided by: qemu-utils_2.11+dfsg-1ubuntu7_amd64
qemu-nbd - QEMU Disk Network Block Device Server
qemu-nbd [OPTION]... filename qemu-nbd -d dev
Export a QEMU disk image using the NBD protocol.
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, log 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, log 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.
Copyright (C) 2006 Anthony Liguori <email@example.com>. This is free software; see the source for copying conditions. There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. 2018-04-11 QEMU-NBD.8(8)