Failed MDADM Array With Ext.4 Partition - "e2fsck: unable to set superblock flags on /dev/md0"
- by Matthew Hodgkins
Had a power failure and now my mdadm array is having problems.
sudo mdadm -D /dev/md0
[hodge@hodge-fs ~]$ sudo mdadm -D /dev/md0
/dev/md0:
Version : 0.90
Creation Time : Sun Apr 25 01:39:25 2010
Raid Level : raid5
Array Size : 8790815232 (8383.57 GiB 9001.79 GB)
Used Dev Size : 1465135872 (1397.26 GiB 1500.30 GB)
Raid Devices : 7
Total Devices : 7
Preferred Minor : 0
Persistence : Superblock is persistent
Update Time : Sat Aug 7 19:10:28 2010
State : clean, degraded, recovering
Active Devices : 6
Working Devices : 7
Failed Devices : 0
Spare Devices : 1
Layout : left-symmetric
Chunk Size : 128K
Rebuild Status : 10% complete
UUID : 44a8f730:b9bea6ea:3a28392c:12b22235 (local to host hodge-fs)
Events : 0.1307608
Number Major Minor RaidDevice State
0 8 81 0 active sync /dev/sdf1
1 8 97 1 active sync /dev/sdg1
2 8 113 2 active sync /dev/sdh1
3 8 65 3 active sync /dev/sde1
4 8 49 4 active sync /dev/sdd1
7 8 33 5 spare rebuilding /dev/sdc1
6 8 16 6 active sync /dev/sdb
sudo mount -a
[hodge@hodge-fs ~]$ sudo mount -a
mount: wrong fs type, bad option, bad superblock on /dev/md0,
missing codepage or helper program, or other error
In some cases useful info is found in syslog - try
dmesg | tail or so
sudo fsck.ext4 /dev/md0
[hodge@hodge-fs ~]$ sudo fsck.ext4 /dev/md0
e2fsck 1.41.12 (17-May-2010)
fsck.ext4: Group descriptors look bad... trying backup blocks...
/dev/md0: recovering journal
fsck.ext4: unable to set superblock flags on /dev/md0
sudo dumpe2fs /dev/md0 | grep -i superblock
[hodge@hodge-fs ~]$ sudo dumpe2fs /dev/md0 | grep -i superblock
dumpe2fs 1.41.12 (17-May-2010)
Primary superblock at 0, Group descriptors at 1-524
Backup superblock at 32768, Group descriptors at 32769-33292
Backup superblock at 98304, Group descriptors at 98305-98828
Backup superblock at 163840, Group descriptors at 163841-164364
Backup superblock at 229376, Group descriptors at 229377-229900
Backup superblock at 294912, Group descriptors at 294913-295436
Backup superblock at 819200, Group descriptors at 819201-819724
Backup superblock at 884736, Group descriptors at 884737-885260
Backup superblock at 1605632, Group descriptors at 1605633-1606156
Backup superblock at 2654208, Group descriptors at 2654209-2654732
Backup superblock at 4096000, Group descriptors at 4096001-4096524
Backup superblock at 7962624, Group descriptors at 7962625-7963148
Backup superblock at 11239424, Group descriptors at 11239425-11239948
Backup superblock at 20480000, Group descriptors at 20480001-20480524
Backup superblock at 23887872, Group descriptors at 23887873-23888396
Backup superblock at 71663616, Group descriptors at 71663617-71664140
Backup superblock at 78675968, Group descriptors at 78675969-78676492
Backup superblock at 102400000, Group descriptors at 102400001-102400524
Backup superblock at 214990848, Group descriptors at 214990849-214991372
Backup superblock at 512000000, Group descriptors at 512000001-512000524
Backup superblock at 550731776, Group descriptors at 550731777-550732300
Backup superblock at 644972544, Group descriptors at 644972545-644973068
Backup superblock at 1934917632, Group descriptors at 1934917633-1934918156
sudo e2fsck -b 32768 /dev/md0
[hodge@hodge-fs ~]$ sudo e2fsck -b 32768 /dev/md0
e2fsck 1.41.12 (17-May-2010)
/dev/md0: recovering journal
e2fsck: unable to set superblock flags on /dev/md0
sudo dmesg | tail
[hodge@hodge-fs ~]$ sudo dmesg | tail
EXT4-fs (md0): ext4_check_descriptors: Checksum for group 0 failed (59837!=29115)
EXT4-fs (md0): group descriptors corrupted!
EXT4-fs (md0): ext4_check_descriptors: Checksum for group 0 failed (59837!=29115)
EXT4-fs (md0): group descriptors corrupted!
Please Help!!!
