Hi Wictor, Hi List I'm more or less stuck with the same problem as you. Btrfs on my external drive got corrupted after I moved a lot of files to it and would'n mount anymore. This happened to me in november 2015 and I haven't tried again since today, as tools and code have matured eventually. I tried a lot of things, but nothing helped yet :-/ $ uname -a > Linux apc01 4.10.13-1-ARCH #1 SMP PREEMPT Thu Apr 27 12:15:09 CEST 2017 x86_64 GNU/Linux $ [root@apc01 ~]# btrfs --version > btrfs-progs v4.11.1 $ btrfs fi sh > Label: 'external_0001' uuid: 6acf5972-91a8-49a1-a5a1-2bcd86b8eb8b > Total devices 1 FS bytes used 2.18TiB > devid 1 size 3.64TiB used 2.19TiB path /dev/mapper/roverlay 1. cloned the drive with dd 2. attached the cloned drive to my computer and created an writable overlay (with losetup and dmsetup), so I can test many things without changing one bit on the cloned drive 3. tried recovery 3a) `mount -t btrfs /dev/mapper/roverlay /mnt` > BTRFS info (device dm-0): disk space caching is enabled > BTRFS info (device dm-0): has skinny extents > BTRFS error (device dm-0): bad tree block start 11851697049360863559 21053440 > BTRFS error (device dm-0): bad tree block start 7989935996922551463 21053440 > BTRFS error (device dm-0): failed to read chunk tree: -5 > BTRFS error (device dm-0): open_ctree failed 3b) `mount -t btrfs -o ro,recovery /dev/mapper/roverlay /mnt` same as 3a) 3c) `btrfs rescue zero-log /dev/mapper/roverlay` > checksum verify failed on 21053440 found 42E96418 wanted 277C3E6A > checksum verify failed on 21053440 found 42E96418 wanted 277C3E6A > checksum verify failed on 21053440 found CF3B13F9 wanted 4A9A0385 > checksum verify failed on 21053440 found 42E96418 wanted 277C3E6A > bytenr mismatch, want=21053440, have=11851697049360863559 > Couldn't read chunk tree > ERROR: cannot open ctree 3d) `btrfs restore /dev/mapper/roverlay /data/recovery` > checksum verify failed on 21053440 found 42E96418 wanted 277C3E6A > checksum verify failed on 21053440 found 42E96418 wanted 277C3E6A > checksum verify failed on 21053440 found CF3B13F9 wanted 4A9A0385 > checksum verify failed on 21053440 found 42E96418 wanted 277C3E6A > bytenr mismatch, want=21053440, have=11851697049360863559 > Couldn't read chunk tree > Could not open root, trying backup super > checksum verify failed on 21053440 found 42E96418 wanted 277C3E6A > checksum verify failed on 21053440 found 42E96418 wanted 277C3E6A > checksum verify failed on 21053440 found CF3B13F9 wanted 4A9A0385 > checksum verify failed on 21053440 found 42E96418 wanted 277C3E6A > bytenr mismatch, want=21053440, have=11851697049360863559 > Couldn't read chunk tree > Could not open root, trying backup super > checksum verify failed on 21053440 found 42E96418 wanted 277C3E6A > checksum verify failed on 21053440 found 42E96418 wanted 277C3E6A > checksum verify failed on 21053440 found CF3B13F9 wanted 4A9A0385 > checksum verify failed on 21053440 found 42E96418 wanted 277C3E6A > bytenr mismatch, want=21053440, have=11851697049360863559 > Couldn't read chunk tree > Could not open root, trying backup super 3e) `btrfs check -s 0 /dev/mapper/roverlay` > using SB copy 0, bytenr 65536 > checksum verify failed on 21053440 found 42E96418 wanted 277C3E6A > checksum verify failed on 21053440 found 42E96418 wanted 277C3E6A > checksum verify failed on 21053440 found CF3B13F9 wanted 4A9A0385 > checksum verify failed on 21053440 found 42E96418 wanted 277C3E6A > bytenr mismatch, want=21053440, have=11851697049360863559 > Couldn't read chunk tree > ERROR: cannot open file system 3f) `btrfs check -s 1 /dev/mapper/roverlay` > using SB copy 1, bytenr 67108864 > checksum verify failed on 21053440 found 42E96418 wanted 277C3E6A > checksum verify failed on 21053440 found 42E96418 wanted 277C3E6A > checksum verify failed on 21053440 found CF3B13F9 wanted 4A9A0385 > checksum verify failed on 21053440 found 42E96418 wanted 277C3E6A > bytenr mismatch, want=21053440, have=11851697049360863559 > Couldn't read chunk tree > ERROR: cannot open file system 3g) `btrfs check -s 2 /dev/mapper/roverlay` > using SB copy 2, bytenr 274877906944 > checksum verify failed on 21053440 found 42E96418 wanted 277C3E6A > checksum verify failed on 21053440 found 42E96418 wanted 277C3E6A > checksum verify failed on 21053440 found CF3B13F9 wanted 4A9A0385 > checksum verify failed on 21053440 found 42E96418 wanted 277C3E6A > bytenr mismatch, want=21053440, have=11851697049360863559 > Couldn't read chunk tree > ERROR: cannot open file system 3h) `btrfs rescue super-recover -v /dev/mapper/roverlay` > All Devices: > Device: id = 1, name = /dev/mapper/roverlay > > Before Recovering: > [All good supers]: > device name = /dev/mapper/roverlay > superblock bytenr = 65536 > > device name = /dev/mapper/roverlay > superblock bytenr = 67108864 > > device name = /dev/mapper/roverlay > superblock bytenr = 274877906944 > > [All bad supers]: > > All supers are valid, no need to recover 3i) `btrfs rescue chunk-recover -v /dev/mapper/roverlay` > All Devices: > Device: id = 1, name = /dev/mapper/roverlay > > Scanning: 2127447805952 in dev0chunk-recover.c:129: process_extent_buffer: BUG_ON `exist->nmirrors >= BTRFS_MAX_MIRRORS` triggered, value 1 > btrfs[0x463150] > btrfs[0x463fd1] > /usr/lib/libpthread.so.0(+0x7297)[0x7f0efc75a297] > /usr/lib/libc.so.6(clone+0x3f)[0x7f0efc49b1ef] > Aborted (core dumped) Any more suggestions? - andre On 02.07.2017 20:21, Wictor Lund wrote: > Hi! > > I cannot mount my filesystem anymore. The problem started with it going > into read-only mode after the filesystem accidentally became full. At > some point the system crashed and after that I got this error. Is it > possible to recover the filesystem or at least recover some data from > it? > > Here is some information from the system: > > $ uname -a > Linux localhost.localdomain 4.8.6-300.fc25.x86_64 #1 SMP Tue Nov 1 12:36:38 UTC 2016 x86_64 x86_64 x86_64 GNU/Linux > > $ btrfs --version > btrfs-progs v4.6.1 > > $ sudo mount /dev/sda4 /mnt > mount: wrong fs type, bad option, bad superblock on /dev/sda4, > missing codepage or helper program, or other error > > In some cases useful info is found in syslog - try > dmesg | tail or so. > > $ sudo btrfs fi show > Label: 'fedora' uuid: 3ddc9cf1-ff3f-4081-900a-4f732838c31b > Total devices 1 FS bytes used 208.67GiB > devid 1 size 230.04GiB used 212.06GiB path /dev/sda4 > > $ dmesg | grep -i btrfs > [ 5.747551] Btrfs loaded, crc32c=crc32c-intel > [ 5.748632] BTRFS: device label fedora devid 1 transid 649633 /dev/sda4 > [ 48.663727] BTRFS info (device sda4): disk space caching is enabled > [ 48.665184] BTRFS error (device sda4): bad tree block start 0 1234052513792 > [ 48.665194] BTRFS warning (device sda4): failed to read tree root > [ 48.680625] BTRFS: open_ctree failed > > $ sudo btrfs check /dev/sda4 > checksum verify failed on 1234052513792 found E4E3BDB6 wanted 00000000 > checksum verify failed on 1234052513792 found E4E3BDB6 wanted 00000000 > bytenr mismatch, want=1234052513792, have=0 > Couldn't read tree root > Couldn't open file system > > $ sudo btrfs restore -l /dev/sda4 > checksum verify failed on 1234052513792 found E4E3BDB6 wanted 00000000 > checksum verify failed on 1234052513792 found E4E3BDB6 wanted 00000000 > bytenr mismatch, want=1234052513792, have=0 > Couldn't read tree root > Could not open root, trying backup super > checksum verify failed on 1234052513792 found E4E3BDB6 wanted 00000000 > checksum verify failed on 1234052513792 found E4E3BDB6 wanted 00000000 > bytenr mismatch, want=1234052513792, have=0 > Couldn't read tree root > Could not open root, trying backup super > Superblock bytenr is larger than device size > Could not open root, trying backup super > > -- > Wictor Lund -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
