Hey,
I just wanted to ask if it's maybe possible to restore data from an old,
failed, raid5 btrfs fs. There are some files on it which I lost lately
and before I format the drives I wanted to give it another shot after
some (6?) years.
I'm not sure what I tried before, but there are 3 drives there, was 4
before but 1 died (and this seems to be the problem of the disaster).
I tried to add 1 new, but that didn't worked.
So, there are 3 devices and as far as I understand, there are still no
good tools to rescue data from them, are they? btrfs restore and other
seems only compatible with 1 drive.
But maybe someone can give me a hint what I can try before giving up.
If I try to mount:
mount -o
degraded,subvol=data,ro,device=/dev/mapper/sdb,device=/dev/mapper/sdd,device=/dev/mapper/sde
/dev/mapper/sde /mnt/test
dmesg give this errors:
BTRFS warning (device dm-4): suspicious: generation <
chunk_root_generation: 176279 < 176413
BTRFS info (device dm-4): allowing degraded mounts
BTRFS info (device dm-4): disk space caching is enabled
BTRFS warning (device dm-4): devid 4 uuid
16490fb1-df5e-4c81-9c07-4f799d0fc132 is missing
BTRFS warning (device dm-4): devid 5 uuid
36436209-c0d4-4a5e-9176-d44c94cb4b39 is missing
BTRFS critical (device dm-4): corrupt leaf: block=1095416938496 slot=151
extent bytenr=1095389085696 len=16384 invalid generation, have 176581
expect (0, 176280]
BTRFS error (device dm-4): block=1095416938496 read time tree block
corruption detected
BTRFS critical (device dm-4): corrupt leaf: block=1095416938496 slot=151
extent bytenr=1095389085696 len=16384 invalid generation, have 176581
expect (0, 176280]
BTRFS error (device dm-4): block=1095416938496 read time tree block
corruption detected
BTRFS warning (device dm-4): failed to read root (objectid=4): -5
BTRFS error (device dm-4): open_ctree failed
(usebackuproot changed nothing and super-recover prints "All supers are
valid, no need to recover")
Do you have any hint, advice to get (some of) this data back?
Best,
Michael
