"If it looks like there is an issue with the filesystem's
superblock. By running the command below we can check for the location of where
backup superblocks will be:
mkfs.ext3 -n /dev/mapper/vg01-lvol5
The mkfs command may cause you some worry, but I'd like
to stress the importance of -n option. This causes it to not actually perform
any changes. Here is an excerpt from the mkfs.ext3 man page:
-n Causes mke2fs to not actually create a
filesystem, but display
what
it would do if it were to create a filesystem.
This can be
used
to determine the location of the backup superblocks for a
particular filesystem, so
long as the mke2fs parameters
that
were
passed when the filesystem was originally created are used
again. (With the -n option added,
of course!)
After this we can look for the lines simlar to:
Superblock backups stored on blocks:
32768, 98304,
163840, 229376, 294912, 819200, 884736, 1605632
Take the first value, i.e. 32768 and try using the
commands I previously pasted with the -b option.
Once again confirm that the operation to be performed
looks sane, keeping in mind to replace 32768 with your actual value:
fsck -b 32768 -fN /dev/mapper/vg01-lvol5
Then if it looks good try with:
fsck -b 32768 -fy /dev/mapper/vg01-lvol5
If you find the first backup superblock does not work try
again with the next available one, i.e. 98304.
Again please make sure to have the filesystem unmounted."
