Re: BTRFS partition corrupted after deleting files in /home
On Mon, Jan 4, 2021 at 6:59 AM Sreyan Chakravarty <sreyan32(a)gmail.com> wrote:
On Mon, Jan 4, 2021 at 1:16 AM Chris Murphy <lists(a)colorremedies.com> wrote:
>
> Try to mount normally, then:
I am unable to mount normally :
# mount -t btrfs /dev/mapper/dm_crypt /mnt/
mount: /mnt: wrong fs type, bad option, bad superblock on
/dev/mapper/dm_crypt, missing codepage or helper program, or other
error.
>
> dmesg
This is what I get in dmesg:
[29867.234062] BTRFS info (device dm-4): disk space caching is enabled
[29867.234067] BTRFS info (device dm-4): has skinny extents
[29867.317955] BTRFS error (device dm-4): parent transid verify failed
on 55640064 wanted 44146 found 44438
[29867.326701] BTRFS error (device dm-4): parent transid verify failed
on 55640064 wanted 44146 found 44438
[29867.326727] BTRFS warning (device dm-4): failed to read root (objectid=9): -5
[29867.333668] BTRFS error (device dm-4): open_ctree failed
transid errors like this indicate out of order writes due to drive
firmware not honoring file system write ordering and then getting a
badly timed crash/powerfail/shutdown. However...
You report that the file system went read only while using it. This
suggests a dropped write and the file system went read-only to limit
the damage. Ideally we'd get the log, if it made it to disk, to see
what lead up to this so we can determine what the problem is and get
it fixed. What I can tell you is this is not user error but that's not
much comfort.
> btrfs check --readonly
A lot of errors, could not even upload to pastebin.
This is in my Google Drive:
https://drive.google.com/file/d/1dpW7aftB3FuD8i1J7d4nRrzZHaGF4vuN/view?us...
Yeah that's bad. I think it's fixable. We need to get a metadata dump
of the file system to see if fsck will fix it.
btrfs-image -c9 -t4 /dev/sdXY /mnt/path/to/file
That will include filenames but not any data. If you need to mask
filenames, add -ss option to the above. (-s won't help here). And the
path to file if you're on a live USB stick can just be something like
~/sreyan-btrfs.img and then put it up on the google drive. By the way
I'm on irc.freenode.net as cmurf that's usually the easier way to get
help, on #fedora channel.
Also, have you ever done a balance on this file system? (That is not a
suggestion that you should or shouldn't have. Just a yes or no
question to try and piece together some other data points.)
--
Chris Murphy