How to roll back btrfs filesystem a few revisions?

Marc MERLIN
2020-02-21T23:17:46Z

On Fri, Feb 21, 2020 at 03:07:40PM -0800, Marc MERLIN wrote:
> And now for extra points, this also damaged a 2nd of my filesystems on the same VG :(
> [64723.601630] BTRFS error (device dm-17): bad tree block start, want 5782272294912 have 0
> [64723.628708] BTRFS error (device dm-17): bad tree block start, want 5782272294912 have 0
> [64897.028176] BTRFS error (device dm-13): parent transid verify failed on 22724608 wanted 10005 found 10001
> [64897.080355] BTRFS error (device dm-13): parent transid verify failed on 22724608 wanted 10005 found 10001

While I'm going to destroy and recreate one of the two filesystems, the
other one has lots of of btrfs relationships I really don't want to lose
and have to re-create.

I'm sure it got in a bad state because it got write denied when trying
to write.
I don't care about last data written, is there a clean way to open the
filesystem and revert it a few revisions?
Basically I want
git reset --hard HEAD^ or HEAD^^

I'm ok with data loss, I just want to get back to a previous good known
consistent state. If I've not disabled COW (which I have not), this
should be possible, correct?

If so, how to I proceed?

Thanks,
Marc
--
"A mouse is a device used to point at the xterm you want to type in" - A.S.R.

Home page: http://marc.merlins.org/