After upgrading my SLES from 11SP3 to 12SP1 I found out that the / root file system is still ext3 as it was before.
I think that's why I can't use snapshots on /

snapper create-config -f ext3 /
Creating config failed (invalid filesystem type).

From https://www.suse.com/documentation/s...ems_major.html
I read that:
To convert the file system to Btrfs, take the file system offline, then enter:
sudo btrfs-convert <device>

But I can't umount / !!!

Is there any way to have snapper working on my system?
Is there any way to convert my ext4 / to btrfs ( leaving the system bootable and working ) ?

Thanks a lot,