On Wed, Mar 15, 2023 at 05:05:49PM +0100, Michael Lee wrote:
Is there a way to fix this, or is a re-installation the only remedy?
For all the things people like about btrfs, IME it's not as good at recovery from adverse events as are ext4 or xfs. In your circumstance your best bet is probably a reinstall. (Hopefully from backups to make this easier, as was suggested several days ago but shouted down for no apparent reason.)
A step to try if you haven't already is to try to run "btrfs check" on the filesystem from the initramfs prompt. There's a --repair option which you may be able to add to correct the problem if the check can identify what's wrong.
Your last hope option would be to boot from an install cd in recovery mode or a live cd and to see if that version of "btrfs check" can fix it. The newer the boot media, the later the version of the btrfs-progs package and (probably) the better it will do at recovery. bullseye is version 5.x, bookworm or bullseye-backports have version 6.x.
