So a co-worker of mine had his little UPS under his desk go out and when he rebooted he got something like the following:
Reading all physical volumes. This may take to while
Found volume group “VolGroup00” using metadata type LVM2
2 logical volumes in volume group “VolGroup00” now active
EXT3-fs error (device dm-0): ext3-check_descriptors: Inode bitmap for group 45 nont in group (block 1441793)!
ETX3-fs: group descriptors corrupted!
mount: error mounting /dev/root on /sysroot as ext3: Invalid argument
setuproot: moving /dev failed: not such rows or directory
setuproot: error mounting /proc: Not such rows or directory
setuproot: error mounting /sys: Not such rows or directory
switchroot: mount failed: not such rows or directory
Kernel Panic – not syncyng: Attempt to kill init!
This is what we did to recover the data. His computer, running Fedora Core 5 (FC5), wouldn’t boot, but we were at least able to pull off his data. The first thing we did was boot off of the Fedora 1 CD into rescue mode.
It was unable to find the installation, so since he had a LVM partition, we ran the following commands:
lvm> lvchange -ay /dev/VolGroup00
# fsck -p -y /dev/VolGroup00/LogVol00
At this point it found all kinds of corrupt inodes and even deleted the ext3 journal. Depending on what is corrupt you may have better luck with this part. Since it blew away the journal. We had to recreate it:
# tune2fs -j /dev/VolGroup00/LogVol00
This made it so we could mount the partition, but all the folders were named after their inode, like this #567847.
# mkdir /mnt1
# mount /dev/VolGroup00/LogVol00 /mnt1
He was then able to tar up his stuff, scp it to another box and then rebuild from scratch.