File System will not Mount
If a Linux filesystem fails to mount, then use the fsck tool to quickly verify that it it not corrupt:
If a Linux filesystem fails to mount, then use the fsck tool to .. verify that it it not corrupt
$ fsck -v /dev/sd<filesystem designator>
If no problems are reported, but the filesystem still will not mount, then you can run a check on the disc sectors (-this will take a while - and the bigger the disc, the longer the time):
$ fsck -c /dev/sd<filesystem designator>
If problems persist - the problem may be a corrupt superblock. List out the location of the superblock and any backups using:
$ mke2fs -n /dev/sd<filesystem designator>
The output will list the current superblock location along with all the backup locations. The format will be something like:
32768 98304 163840 229376 294912 ..etc...
You can now direct Linux to use one of the superblock backups listed above using:
$ fsck -b <alternative superblock> /dev/sd<filesystem designator>
If the first one doesn't work - try one of the others.
Note: always ensure the filesystem is umounted before running fsck or mke2efs