diff options
Diffstat (limited to 'qemu-img.texi')
| -rw-r--r-- | qemu-img.texi | 25 |
1 files changed, 23 insertions, 2 deletions
diff --git a/qemu-img.texi b/qemu-img.texi index 8b05f2c428..60b83fc11a 100644 --- a/qemu-img.texi +++ b/qemu-img.texi @@ -28,6 +28,10 @@ Command parameters: is the disk image format. It is guessed automatically in most cases. See below for a description of the supported disk formats. +@item --backing-chain +will enumerate information about backing files in a disk image chain. Refer +below for further description. + @item size is the disk image size in bytes. Optional suffixes @code{k} or @code{K} (kilobyte, 1024) @code{M} (megabyte, 1024k) and @code{G} (gigabyte, 1024M) @@ -129,7 +133,7 @@ created as a copy on write image of the specified base image; the @var{backing_file} should have the same content as the input's base image, however the path, image format, etc may differ. -@item info [-f @var{fmt}] [--output=@var{ofmt}] @var{filename} +@item info [-f @var{fmt}] [--output=@var{ofmt}] [--backing-chain] @var{filename} Give information about the disk image @var{filename}. Use it in particular to know the size reserved on disk which can be different @@ -137,6 +141,21 @@ from the displayed size. If VM snapshots are stored in the disk image, they are displayed too. The command can output in the format @var{ofmt} which is either @code{human} or @code{json}. +If a disk image has a backing file chain, information about each disk image in +the chain can be recursively enumerated by using the option @code{--backing-chain}. + +For instance, if you have an image chain like: + +@example +base.qcow2 <- snap1.qcow2 <- snap2.qcow2 +@end example + +To enumerate information about each disk image in the above chain, starting from top to base, do: + +@example +qemu-img info --backing-chain snap2.qcow2 +@end example + @item snapshot [-l | -a @var{snapshot} | -c @var{snapshot} | -d @var{snapshot} ] @var{filename} List, apply, create or delete snapshots in image @var{filename}. @@ -148,7 +167,9 @@ Changes the backing file of an image. Only the formats @code{qcow2} and The backing file is changed to @var{backing_file} and (if the image format of @var{filename} supports this) the backing file format is changed to -@var{backing_fmt}. +@var{backing_fmt}. If @var{backing_file} is specified as ``'' (the empty +string), then the image is rebased onto no backing file (i.e. it will exist +independently of any backing file). There are two different modes in which @code{rebase} can operate: @table @option |