]> git.proxmox.com Git - mirror_qemu.git/blob - qemu-nbd.texi
qemu-nbd: support internal snapshot export
[mirror_qemu.git] / qemu-nbd.texi
1 @example
2 @c man begin SYNOPSIS
3 usage: qemu-nbd [OPTION]... @var{filename}
4 @c man end
5 @end example
6
7 @c man begin DESCRIPTION
8
9 Export QEMU disk image using NBD protocol.
10
11 @c man end
12
13 @c man begin OPTIONS
14 @table @option
15 @item @var{filename}
16 is a disk image filename
17 @item -p, --port=@var{port}
18 port to listen on (default @samp{1024})
19 @item -o, --offset=@var{offset}
20 offset into the image
21 @item -b, --bind=@var{iface}
22 interface to bind to (default @samp{0.0.0.0})
23 @item -k, --socket=@var{path}
24 Use a unix socket with path @var{path}
25 @item -r, --read-only
26 export read-only
27 @item -P, --partition=@var{num}
28 only expose partition @var{num}
29 @item -s, --snapshot
30 use @var{filename} as an external snapshot, create a temporary
31 file with backing_file=@var{filename}, redirect the write to
32 the temporary one
33 @item -l, --load-snapshot=@var{snapshot_param}
34 load an internal snapshot inside @var{filename} and export it
35 as an read-only device, @var{snapshot_param} format is
36 'snapshot.id=[ID],snapshot.name=[NAME]' or '[ID_OR_NAME]'
37 @item -n, --nocache
38 @itemx --cache=@var{cache}
39 set cache mode to be used with the file. See the documentation of
40 the emulator's @code{-drive cache=...} option for allowed values.
41 @item --aio=@var{aio}
42 choose asynchronous I/O mode between @samp{threads} (the default)
43 and @samp{native} (Linux only).
44 @item --discard=@var{discard}
45 toggles whether @dfn{discard} (also known as @dfn{trim} or @dfn{unmap})
46 requests are ignored or passed to the filesystem. The default is no
47 (@samp{--discard=ignore}).
48 @item -c, --connect=@var{dev}
49 connect @var{filename} to NBD device @var{dev}
50 @item -d, --disconnect
51 disconnect the specified device
52 @item -e, --shared=@var{num}
53 device can be shared by @var{num} clients (default @samp{1})
54 @item -f, --format=@var{fmt}
55 force block driver for format @var{fmt} instead of auto-detecting
56 @item -t, --persistent
57 don't exit on the last connection
58 @item -v, --verbose
59 display extra debugging information
60 @item -h, --help
61 display this help and exit
62 @item -V, --version
63 output version information and exit
64 @end table
65
66 @c man end
67
68 @ignore
69
70 @setfilename qemu-nbd
71 @settitle QEMU Disk Network Block Device Server
72
73 @c man begin AUTHOR
74 Copyright (C) 2006 Anthony Liguori <anthony@codemonkey.ws>.
75 This is free software; see the source for copying conditions. There is NO
76 warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
77 @c man end
78
79 @c man begin SEEALSO
80 qemu-img(1)
81 @c man end
82
83 @end ignore