qemu-img.texi

   1 @example
   2 @c man begin SYNOPSIS
   3 usage: qemu-img command [command options]
   4 @c man end
   5 @end example
   6
   7 @c man begin OPTIONS
   8
   9 The following commands are supported:
  10 @table @option
  11 @item create [-e] [-6] [-F @var{base_fmt}] [-b @var{base_image}] [-f @var{fmt}] @var{filename} [@var{size}]
  12 @item commit [-f @var{fmt}] @var{filename}
  13 @item convert [-c] [-e] [-6] [-f @var{fmt}] [-O @var{output_fmt}] [-B @var{output_base_image}] @var{filename} [@var{filename2} [...]] @var{output_filename}
  14 @item info [-f @var{fmt}] @var{filename}
  15 @item snapshot [-l | -a @var{snapshot} | -c @var{snapshot} | -d @var{snapshot}] @var{filename}
  16 @end table
  17
  18 Command parameters:
  19 @table @var
  20 @item filename
  21  is a disk image filename
  22 @item base_image
  23 is the read-only disk image which is used as base for a copy on
  24     write image; the copy on write image only stores the modified data
  25 @item output_base_image
  26 forces the output image to be created as a copy on write
  27 image of the specified base image; @code{output_base_image} should have the same
  28 content as the input's base image, however the path, image format, etc may
  29 differ
  30 @item base_fmt
  31 is the disk image format of @var{base_image}. for more information look at @var{fmt}
  32 @item fmt
  33 is the disk image format. It is guessed automatically in most cases. The following formats are supported:
  34
  35 @table @code
  36 @item raw
  37
  38 Raw disk image format (default). This format has the advantage of
  39 being simple and easily exportable to all other emulators. If your
  40 file system supports @emph{holes} (for example in ext2 or ext3 on
  41 Linux or NTFS on Windows), then only the written sectors will reserve
  42 space. Use @code{qemu-img info} to know the real size used by the
  43 image or @code{ls -ls} on Unix/Linux.
  44
  45 @item qcow2
  46 QEMU image format, the most versatile format. Use it to have smaller
  47 images (useful if your filesystem does not supports holes, for example
  48 on Windows), optional AES encryption, zlib based compression and
  49 support of multiple VM snapshots.
  50 @item qcow
  51 Old QEMU image format. Left for compatibility.
  52 @item cow
  53 User Mode Linux Copy On Write image format. Used to be the only growable
  54 image format in QEMU. It is supported only for compatibility with
  55 previous versions. It does not work on win32.
  56 @item vmdk
  57 VMware 3 and 4 compatible image format.
  58 @item cloop
  59 Linux Compressed Loop image, useful only to reuse directly compressed
  60 CD-ROM images present for example in the Knoppix CD-ROMs.
  61 @end table
  62
  63 @item size
  64 is the disk image size in kilobytes. Optional suffixes @code{M}
  65 (megabyte, 1024 * 1024) and @code{G} (gigabyte, 1024 * 1024 * 1024)
  66 are supported and any @code{k} or @code{K} is ignored.
  67
  68 @item output_filename
  69 is the destination disk image filename
  70
  71 @item output_fmt
  72  is the destination format
  73
  74 @item -c
  75 indicates that target image must be compressed (qcow format only)
  76 @item -e
  77 indicates that the target image must be encrypted (qcow format only)
  78 @item -6
  79 indicates that the target image must use compatibility level 6 (vmdk format only)
  80 @item -h
  81 with or without a command shows help and lists the supported formats
  82 @end table
  83
  84 Parameters to snapshot subcommand:
  85
  86 @table @option
  87
  88 @item snapshot
  89 is the name of the snapshot to create, apply or delete
  90 @item -a
  91 applies a snapshot (revert disk to saved state)
  92 @item -c
  93 creates a snapshot
  94 @item -d
  95 deletes a snapshot
  96 @item -l
  97 lists all snapshots in the given image
  98 @end table
  99
 100 Command description:
 101
 102 @table @option
 103 @item create [-6] [-e] [-b @var{base_image}] [-f @var{fmt}] @var{filename} [@var{size}]
 104
 105 Create the new disk image @var{filename} of size @var{size} and format
 106 @var{fmt}.
 107
 108 If @var{base_image} is specified, then the image will record only the
 109 differences from @var{base_image}. No size needs to be specified in
 110 this case. @var{base_image} will never be modified unless you use the
 111 @code{commit} monitor command.
 112
 113 @item commit [-f @var{fmt}] @var{filename}
 114
 115 Commit the changes recorded in @var{filename} in its base image.
 116
 117 @item convert [-c] [-e] [-f @var{fmt}] @var{filename} [-O @var{output_fmt}] @var{output_filename}
 118
 119 Convert the disk image @var{filename} to disk image @var{output_filename}
 120 using format @var{output_fmt}. It can be optionally encrypted
 121 (@code{-e} option) or compressed (@code{-c} option).
 122
 123 Only the format @code{qcow} supports encryption or compression. The
 124 compression is read-only. It means that if a compressed sector is
 125 rewritten, then it is rewritten as uncompressed data.
 126
 127 Encryption uses the AES format which is very secure (128 bit keys). Use
 128 a long password (16 characters) to get maximum protection.
 129
 130 Image conversion is also useful to get smaller image when using a
 131 growable format such as @code{qcow} or @code{cow}: the empty sectors
 132 are detected and suppressed from the destination image.
 133
 134 @item info [-f @var{fmt}] @var{filename}
 135
 136 Give information about the disk image @var{filename}. Use it in
 137 particular to know the size reserved on disk which can be different
 138 from the displayed size. If VM snapshots are stored in the disk image,
 139 they are displayed too.
 140
 141 @item snapshot [-l | -a @var{snapshot} | -c @var{snapshot} | -d @var{snapshot} ] @var{filename}
 142
 143 List, apply, create or delete snapshots in image @var{filename}.
 144 @end table
 145
 146 @c man end
 147
 148 @ignore
 149
 150 @setfilename qemu-img
 151 @settitle QEMU disk image utility
 152
 153 @c man begin SEEALSO
 154 The HTML documentation of QEMU for more precise information and Linux
 155 user mode emulator invocation.
 156 @c man end
 157
 158 @c man begin AUTHOR
 159 Fabrice Bellard
 160 @c man end
 161
 162 @end ignore