On 2021-05-26 10:53 a.m., Lentes, Bernd wrote:

OK. Thanks, i will try that and keep you informed.

Bernd

Please note that I made a mistake.


When you snapshot into a new @, it will already have an empty (not
subvolume) @/var/lib/docker/btrfs directory.

You have to get that directory out of the way before you move the
subvolume, otherwise, you'll end up with a  @/var/lib/docker/btrfs/btrfs
and mount will fail.

rmdir /mnt/sub/root-volume/@/var/lib/docker/btrfs

*before* you do:

mv /mnt/sub/root-volume/@bad/var/lib/docker/btrfs
/mnt/sub/root-volume/@/var/lib/docker/btrfs