docs/tools/qemu-storage-daemon.rst

1 .. _storage-daemon:
8 --------
10 **qemu-storage-daemon** [options]
13 -----------
15 ``qemu-storage-daemon`` provides disk image functionality from QEMU,
16 ``qemu-img``, and ``qemu-nbd`` in a long-running process controlled via QMP
19 perform other disk-related operations. The daemon is controlled via a QMP
20 monitor and initial configuration from the command-line.
34 :manpage:`qemu-storage-daemon-qmp-ref(7)` manual page for a description of the
46 -------
48 .. program:: qemu-storage-daemon
52 .. option:: -h, --help
56 .. option:: -V, --version
60 .. option:: -T, --trace [[enable=]PATTERN][,events=FILE][,file=FILE]
62   .. include:: ../qemu-option-trace.rst.inc
64 .. option:: --blockdev BLOCKDEVDEF
67   description of block node properties and the :manpage:`qemu-block-drivers(7)`
68   manual page for a description of driver-specific parameters.
70 .. option:: --chardev CHARDEVDEF
76   --chardev socket,id=char1,path=/var/run/qsd-qmp.sock,server=on,wait=off
78 .. option:: --export [type=]nbd,id=<id>,node-name=<node-name>[,name=<export-name>][,writable=on|off…
79 …--export [type=]vhost-user-blk,id=<id>,node-name=<node-name>,addr.type=unix,addr.path=<socket-path…
80 …--export [type=]vhost-user-blk,id=<id>,node-name=<node-name>,addr.type=fd,addr.str=<fd>[,writable=…
81 …--export [type=]fuse,id=<id>,node-name=<node-name>,mountpoint=<file>[,growable=on|off][,writable=o…
82 …--export [type=]vduse-blk,id=<id>,node-name=<node-name>,name=<vduse-name>[,writable=on|off][,num-q…
84   is a block export definition. ``node-name`` is the block node that should be
88   The ``nbd`` export type requires ``--nbd-server`` (see below). ``name`` is
90   ``node-name``). ``bitmap`` is the name of a dirty bitmap reachable from the
92   metadata context name "qemu:dirty-bitmap:BITMAP" to inspect the bitmap.
94   The ``vhost-user-blk`` export type takes a vhost-user socket address on which
96   ``addr.type=unix,addr.path=<socket-path>`` for UNIX domain sockets and
98   ``logical-block-size`` sets the logical block size in bytes (the default is
99   512). ``num-queues`` sets the number of virtqueues (the default is 1).
109   block node to fit.  The ``allow-other`` option controls whether users other
111   that enabling this option as a non-root user requires enabling the
113   ``allow-other`` to auto (the default) will try enabling this option, and on
116   The ``vduse-blk`` export type takes a ``name`` (must be unique across the host)
118   ``num-queues`` sets the number of virtqueues (the default is 1).
119   ``queue-size`` sets the virtqueue descriptor table size (the default is 256).
132   https://vdpa-dev.gitlab.io/.
135   https://docs.kernel.org/userspace-api/vduse.html.
137 .. option:: --monitor MONITORDEF
143   --monitor chardev=char1
145 .. option:: --nbd-server addr.type=inet,addr.host=<host>,addr.port=<port>[,tls-creds=<id>][,tls-aut…
146 …--nbd-server addr.type=unix,addr.path=<path>[,tls-creds=<id>][,tls-authz=<id>][,max-connections=<n…
147   --nbd-server addr.type=fd,addr.str=<fd>[,tls-creds=<id>][,tls-authz=<id>][,max-connections=<n>]
151   below). TLS encryption can be configured using ``--object`` tls-creds-* and
152   authz-* secrets (see below).
155   ``/var/run/qsd-nbd.sock``::
157   --nbd-server addr.type=unix,addr.path=/var/run/qsd-nbd.sock
159 .. option:: --object help
160   --object <type>,help
161   --object <type>[,<property>=<value>...]
167 .. option:: --pidfile PATH
172     $ kill -SIGTERM $(<path/to/qsd.pid)
181 .. option:: --daemonize
189 --------
193   $ qemu-storage-daemon \
194       --chardev socket,path=qmp.sock,server=on,wait=off,id=char1 \
195       --monitor chardev=char1
214           ['qemu-storage-daemon',
215            '--chardev', f'socket,fd={fd},server=on,id=char1',
216            '--monitor', 'chardev=char1'],
229 The same socket spawning approach also works with the ``--nbd-server
230 addr.type=fd,addr.str=<fd>`` and ``--export
231 type=vhost-user-blk,addr.type=fd,addr.str=<fd>`` options.
235   $ qemu-storage-daemon \
236       --blockdev driver=file,node-name=disk,filename=disk.img \
237       --nbd-server addr.type=unix,addr.path=nbd.sock \
238       --export type=nbd,id=export,node-name=disk,writable=on
240 Export a qcow2 image file ``disk.qcow2`` as a vhost-user-blk device over UNIX
241 domain socket ``vhost-user-blk.sock``::
243   $ qemu-storage-daemon \
244       --blockdev driver=file,node-name=file,filename=disk.qcow2 \
245       --blockdev driver=qcow2,node-name=qcow2,file=file \
246 …--export type=vhost-user-blk,id=export,addr.type=unix,addr.path=vhost-user-blk.sock,node-name=qcow2
251   $ qemu-storage-daemon \
252       --blockdev driver=file,node-name=file,filename=disk.qcow2 \
253       --blockdev driver=qcow2,node-name=qcow2,file=file \
254       --export type=fuse,id=export,node-name=qcow2,mountpoint=disk.qcow2,writable=on
257 --------
259 :manpage:`qemu(1)`, :manpage:`qemu-block-drivers(7)`, :manpage:`qemu-storage-daemon-qmp-ref(7)`