diff --git a/doc/manpages/qvm-volume.rst b/doc/manpages/qvm-volume.rst index e3dafcf2..5ccd5a7d 100644 --- a/doc/manpages/qvm-volume.rst +++ b/doc/manpages/qvm-volume.rst @@ -110,9 +110,25 @@ aliases: extend revert ^^^^^^ -| :command:`qvm-volume revert` [-h] [--verbose] [--quiet] *VMNAME:VOLUME* - -Revert a volume to previous revision. +| :command:`qvm-volume revert` [-h] [--verbose] [--quiet] *VMNAME:VOLUME* [rev] + +Revert a volume to a previous revision. If *rev* is specified, reverts the +volume to that specific revision (discarding the current volume contents +and possibly deleting any newer revisions). If *rev* is not specified, the +contents of the volume are reverted to the latest known revision. Your storage +driver must support revisions and its `revisions_to_keep` property must be +greater than `0`. + +Generally, revisions are only created for volumes which have the `save_on_stop` +property set. Revision creation is storage driver implementation-dependent, +but the general practice is that a revision is only created when a volume is +clean. Paradoxically and despite the `save_on_stop` name, revisions in these +volumes are created prior to its owning qube starting, rather than when its +owning qube stops. + +You may not revert a volume while it is in use. This includes its owning qube +running. With some storage drivers, this also extends to cases when the volume +is currently being exported to use in a `qvm-clone` operation. aliases: rv, r