3 usage: qemu-img command [command options]
9 The following commands are supported:
11 @include qemu-img-cmds.texi
16 is a disk image filename
18 is the read-only disk image which is used as base for a copy on
19 write image; the copy on write image only stores the modified data
20 @item output_base_image
21 forces the output image to be created as a copy on write
22 image of the specified base image; @code{output_base_image} should have the same
23 content as the input's base image, however the path, image format, etc may
26 is the disk image format of @var{base_image}. for more information look at @var{fmt}
28 is the disk image format. It is guessed automatically in most cases. See below
29 for a description of the supported disk formats.
32 is the disk image size in bytes. Optional suffixes @code{k} or @code{K}
33 (kilobyte, 1024) @code{M} (megabyte, 1024k) and @code{G} (gigabyte, 1024M)
34 and T (terabyte, 1024G) are supported. @code{b} is ignored.
37 is the destination disk image filename
40 is the destination format
42 is a comma separated list of format specific options in a
43 name=value format. Use @code{-o ?} for an overview of the options supported
48 indicates that target image must be compressed (qcow format only)
50 with or without a command shows help and lists the supported formats
53 Parameters to snapshot subcommand:
58 is the name of the snapshot to create, apply or delete
60 applies a snapshot (revert disk to saved state)
66 lists all snapshots in the given image
72 @item create [-F @var{base_fmt}] [-b @var{base_image}] [-f @var{fmt}] [-o @var{options}] @var{filename} [@var{size}]
74 Create the new disk image @var{filename} of size @var{size} and format
77 If @var{base_image} is specified, then the image will record only the
78 differences from @var{base_image}. No size needs to be specified in
79 this case. @var{base_image} will never be modified unless you use the
80 @code{commit} monitor command.
82 The size can also be specified using the @var{size} option with @code{-o},
83 it doesn't need to be specified separately in this case.
85 @item commit [-f @var{fmt}] @var{filename}
87 Commit the changes recorded in @var{filename} in its base image.
89 @item convert [-c] [-f @var{fmt}] [-O @var{output_fmt}] [-o @var{options}] [-B @var{output_base_image}] @var{filename} [@var{filename2} [...]] @var{output_filename}
91 Convert the disk image @var{filename} to disk image @var{output_filename}
92 using format @var{output_fmt}. It can be optionally compressed (@code{-c}
93 option) or use any format specific options like encryption (@code{-o} option).
95 Only the formats @code{qcow} and @code{qcow2} support encryption or compression. The
96 compression is read-only. It means that if a compressed sector is
97 rewritten, then it is rewritten as uncompressed data.
99 Encryption uses the AES format which is very secure (128 bit keys). Use
100 a long password (16 characters) to get maximum protection.
102 Image conversion is also useful to get smaller image when using a
103 growable format such as @code{qcow} or @code{cow}: the empty sectors
104 are detected and suppressed from the destination image.
106 @item info [-f @var{fmt}] @var{filename}
108 Give information about the disk image @var{filename}. Use it in
109 particular to know the size reserved on disk which can be different
110 from the displayed size. If VM snapshots are stored in the disk image,
111 they are displayed too.
113 @item snapshot [-l | -a @var{snapshot} | -c @var{snapshot} | -d @var{snapshot} ] @var{filename}
115 List, apply, create or delete snapshots in image @var{filename}.
118 Supported image file formats:
123 Raw disk image format (default). This format has the advantage of
124 being simple and easily exportable to all other emulators. If your
125 file system supports @emph{holes} (for example in ext2 or ext3 on
126 Linux or NTFS on Windows), then only the written sectors will reserve
127 space. Use @code{qemu-img info} to know the real size used by the
128 image or @code{ls -ls} on Unix/Linux.
132 Host device format. This format should be used instead of raw when
133 converting to block devices or other devices where "holes" are not
137 QEMU image format, the most versatile format. Use it to have smaller
138 images (useful if your filesystem does not supports holes, for example
139 on Windows), optional AES encryption, zlib based compression and
140 support of multiple VM snapshots.
142 Old QEMU image format. Left for compatibility.
144 User Mode Linux Copy On Write image format. Used to be the only growable
145 image format in QEMU. It is supported only for compatibility with
146 previous versions. It does not work on win32.
148 VirtualBox 1.1 compatible image format.
150 VMware 3 and 4 compatible image format.
152 Linux Compressed Loop image, useful only to reuse directly compressed
153 CD-ROM images present for example in the Knoppix CD-ROMs.
161 @setfilename qemu-img
162 @settitle QEMU disk image utility
165 The HTML documentation of QEMU for more precise information and Linux
166 user mode emulator invocation.