mount failed to mount CentOS partition from Ubuntu 10.10

[Unmeshj]

Hello all,

Following is the snapshot of my command prompt:

# mount /dev/sdb2 /mnt/
mount: wrong fs type, bad option, bad superblock on /dev/sdb2,
missing codepage or helper program, or other error
In some cases useful info is found in syslog - try
dmesg | tail or so

# dmesg | tail
[ 93.830898] 05 02 40 88
[ 93.830905] sd 5:0:0:0: [sdb] Add. Sense: Unrecovered read error - auto reallocate failed
[ 93.830915] sd 5:0:0:0: [sdb] CDB: Read(10): 28 00 05 02 3f c6 00 01 00 00
[ 93.830931] end_request: I/O error, dev sdb, sector 84033672
[ 93.830956] ata5: EH complete
[ 93.831020] JBD: Failed to read block at offset 15708
[ 93.831031] JBD: recovery failed
[ 93.831035] EXT3-fs (sdb2): error loading journal
[ 105.441810] show_signal_msg: 15 callbacks suppressed
[ 105.441820] gvfsd-metadata[1796]: segfault at 8 ip 0804cb7a sp bfb85f00 error 4 in gvfsd-metadata[8048000+c000]


I would also like to share my partitioning scheme:

# fdisk -l

Disk /dev/sda: 80.0 GB, 80026361856 bytes
255 heads, 63 sectors/track, 9729 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0xb9226c82

Device Boot Start End Blocks Id System
/dev/sda1 * 1 2613 20988891 c W95 FAT32 (LBA)
/dev/sda2 2614 5226 20988922+ 7 HPFS/NTFS
/dev/sda3 5227 7839 20988922+ c W95 FAT32 (LBA)
/dev/sda4 7840 9729 15181394+ f W95 Ext'd (LBA)
/dev/sda5 7840 7923 674698+ 82 Linux swap / Solaris
/dev/sda6 * 7924 8672 6016311 83 Linux
/dev/sda7 8673 9729 8490321 83 Linux

Disk /dev/sdb: 1000.2 GB, 1000204886016 bytes
255 heads, 63 sectors/track, 121601 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x6efe0860

Device Boot Start End Blocks Id System
/dev/sdb1 1 5222 41945683+ 7 HPFS/NTFS
/dev/sdb2 * 5223 10444 41945715 83 Linux
/dev/sdb3 10445 10689 1967962+ 82 Linux swap / Solaris
/dev/sdb4 15667 121601 850922857 f W95 Ext'd (LBA)
/dev/sdb5 15667 18277 20972826 83 Linux
/dev/sdb6 18278 31332 104864256 7 HPFS/NTFS
/dev/sdb7 31333 44387 104864256 7 HPFS/NTFS
/dev/sdb8 44388 121601 620221423+ 7 HPFS/NTFS


Please help what must have gone wrong ?

Thanks and Regards,
Unmesh

[zackwasa]

your partition is corrupted and because of I/O errors it is unreadable

[atreyu]

Yeah, I/O errors are not good. Have you tried mounting it without the journal (aka ext2)? e.g.:

mount -o ro -t ext2 /dev/sdb2 /mnt

Are you sure it is a Linux partition, like the partition table says it is?

mount -o ro -t auto /dev/sdb2

Check on the health of the drive itself with smartctl (part of smartmontools):

smartctl -H /dev/sdb

Lots of info:

smartctl --all /dev/sdb

If you really care about the data on that partition, the first thing you ought to do is shut down the PC, reboot with a Linux DVD into rescue mode and dump the drive (or at least the partition) to a raw file. Then go about trying filesystem checks and etc.