Hi, I'm still trying to restore data from the drive that I have. I'm hoping that someone might be able to help, or provide some advice how I can proceed. It's starting to seem hopeless for this. Thanks for any help you can provide. kareem. On Wed, 29 Jan 2020 at 21:55, Kareem Straker <kareem.straker@xxxxxxxxx> wrote: > > Hi, > > My first mail to the list, so I hope I'm getting this right. > > I'm getting a little despirate trying to recover my Unraid system > btrfs 2-disk cache pool, that seems to be corrupted. The 1st disk > seems to have lost the partition information completely, the 2nd seems > to be present but is not able to mount. Neither disk has been > overwritten as far as I'm aware. Both disks are nvme model Samsung 970 > Evo Plus 250GB. > > Trying to cram info into this mail. > > Can anyone help? Advice? > > When I use any fsck or btrfs tool, I get an error: bad tree block > 479137857536, bytenr mismatch, want=479137857536, have=0 > > I believe the filesystem is there, but seems I need to rebuild the > superblock or tree. > > Any suggestions would be appreciated. > > disk paths: > /dev/nvme0n1p1 > /dev/nvme1n1p1 > > First info + dmesg.log (attached): > ``` > root@blaster:~# uname -a > Linux blaster 4.19.94-Unraid #1 SMP Thu Jan 9 08:20:36 PST 2020 x86_64 > AMD Ryzen 5 3600 6-Core Processor AuthenticAMD GNU/Linux > root@blaster:~# btrfs --version > btrfs-progs v5.4 > root@blaster:~# btrfs fi show > bad tree block 479137857536, bytenr mismatch, want=479137857536, have=0 > Couldn't setup device tree > Label: none uuid: 3d4bca36-f541-4b63-bb84-1745a9a384eb > Total devices 2 FS bytes used 179.16GiB > devid 1 size 232.89GiB used 232.01GiB path /dev/nvme1n1p1 > *** Some devices missing > > root@blaster:~# btrfs fi df /mnt/cache > ERROR: cannot access '/mnt/cache': No such file or directory > ``` > > Extra info: > ``` > root@blaster:~# btrfs check --repair /dev/nvme1n1p1 > enabling repair mode > WARNING: > > Do not use --repair unless you are advised to do so by a developer > or an experienced user, and then only after having accepted that no > fsck can successfully repair all types of filesystem corruption. Eg. > some software or hardware bugs can fatally damage a volume. > The operation will start in 10 seconds. > Use Ctrl-C to stop it. > 10 9 8 7 6 5 4 3 2 1 > Starting repair. > Opening filesystem to check... > bad tree block 479137857536, bytenr mismatch, want=479137857536, have=0 > Couldn't setup device tree > ERROR: cannot open file system > root@blaster:~# > root@blaster:~# > root@blaster:~# btrfs rescue fix-device-size /dev/nvme1n1p1 > bad tree block 479137857536, bytenr mismatch, want=479137857536, have=0 > Couldn't setup device tree > ERROR: could not open btrfs > > ``` > > ``` > root@blaster:~# btrfs rescue super-recover -v /dev/nvme1n1p1 > All Devices: > Device: id = 1, name = /dev/nvme1n1p1 > > Before Recovering: > [All good supers]: > device name = /dev/nvme1n1p1 > superblock bytenr = 65536 > > device name = /dev/nvme1n1p1 > superblock bytenr = 67108864 > > [All bad supers]: > > All supers are valid, no need to recover > ```
