Re: rollback to a snapshot

[remi@georgianit.com]

On Wed, Jun 7, 2023, at 3:37 PM, Bernd Lentes wrote:

> VM images are on host BTRFS and i create the snapshots from them on the host.
>

So there are a couple choices on how you want to restore.

You can make a new snapshot from your 'good' snapshot.  This will roll back the entire subvolume.

mv /subvolume /subvolume-bad
btrfs sub snap /path-to-snapshot /subvolume

When you are confident that you want to delete the replaced subvolume

btrfs sub del /subvolume-bad

*Note*. you might want to first rename sobvolume-bad to something safe, like mv subvolume-bad deleteme; btrfs sub del deleteme
That way, is not not possible to accidentally hit <Enter> when you have btrfs sub del /subvolume on the command line.


Alternatively, you can just copy the disk image file from your snapshot into your active subvolume

cp -a --reflink=always /path-to-snapshot/vm.img /subvolume/vm.img