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Hodge

Member

Registered: 2010-07-04

Posts: 6

Failed MDADM Array With Ext.4 Partition

Hi Guys,

I had a powerfailure and now my MDADM array with Ext4 partition is broken.

The array has now rebuilt but I still can't mount.

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 : Sun Aug  8 07:30:06 2010
          State : clean
 Active Devices : 7
Working Devices : 7
 Failed Devices : 0
  Spare Devices : 0

         Layout : left-symmetric
     Chunk Size : 128K

           UUID : 44a8f730:b9bea6ea:3a28392c:12b22235 (local to host hodge-fs)
         Events : 0.1307880

    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
       5       8       33        5      active sync   /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!

zackboll

Member

Registered: 2010-08-26

Posts: 1

Re: Failed MDADM Array With Ext.4 Partition

I am having the same problem as this guy.  I was copying files over to a raid-5 mdadm ext4 partition and suffered a power loss.  When I booted the system back up, I could rebuild the array, but no longer able to mount the ext4 file system.

Could this have something to do with the delayed block allocation in ext4 when creating files?

Thanks, any help would be appreciated.
Zack

djgera

Developer

From: Buenos Aires - Argentina

Registered: 2008-12-24

Posts: 723

Website

Re: Failed MDADM Array With Ext.4 Partition

Give a tip here is somewhat delicate. Perhaps a tip works perfect in some cases and in one case only worsen the situation.

Have you tried to send an email to linux-ext4 mailing list? There are lots of people involved that may help. http://vger.kernel.org/vger-lists.html#linux-ext4

I hope that you recover all your information.