2

I am trying to recover a disk that has corrupted superblock but I cant seem to unmount the disk at all. I used bcache for the three extra drive after a reboot one of the drive stopped working. so I removed the SSD cache drive and still cant seem to recover the drive

pavs@VAS:~$ lsblk
NAME        MAJ:MIN RM   SIZE RO TYPE MOUNTPOINT
sda           8:0    0 149.1G  0 disk 
├─sda1        8:1    0 133.4G  0 part /
├─sda2        8:2    0     1K  0 part 
└─sda5        8:5    0  15.7G  0 part [SWAP]
sdb           8:16   0   2.7T  0 disk 
└─sdb1        8:17   0   2.7T  0 part 
  └─bcache0 251:0    0   2.7T  0 disk /var/www/html/directlink/FTP1
sdc           8:32   0   1.8T  0 disk 
└─sdc1        8:33   0   1.8T  0 part 
  └─bcache1 251:1    0   1.8T  0 disk 
sdd           8:48   0   1.8T  0 disk 
└─sdd1        8:49   0   1.8T  0 part 
  └─bcache2 251:2    0   1.8T  0 disk



pavs@VAS:~$ sudo fsck.ext4 -v /dev/sdd1
e2fsck 1.42.9 (4-Feb-2014)
/dev/sdd1 is in use.
e2fsck: Cannot continue, aborting.


pavs@VAS:~$ umount -l /dev/sdd
umount: /dev/sdd is not mounted (according to mtab)
pavs@VAS:~$ umount -l /dev/sdd1
umount: /dev/sdd1 is not mounted (according to mtab)


 1072.806897] EXT4-fs (bcache2): ext4_check_descriptors: Checksum for group 640 failed (57199!=0)
[ 1072.806900] EXT4-fs (bcache2): group descriptors corrupted!
bran
  • 629

2 Answers2

0
sudo mke2fs -n /dev/sdd

lists the index number for stored superblocks.

sudo e2fsck -b block_number /dev/sdd

Reboot and the superblock "might" be repaired (sometimes it works sometimes it doesn't). Try all backup superblocks before giving up

jones0610
  • 2,514
0

Try to fix, using backup superblock. Probably you'll need livecd to get around automount / fsck on boot. See instruction shere:

http://linuxexpresso.wordpress.com/2010/03/31/repair-a-broken-ext4-superblock-in-ubuntu/

ulcha
  • 464