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Emergency Disk Recovery on Linux

While developing a script for Oracle Enterprise Manager (OEM) that checks the file system on our servers, I saw the /var on my (NIS) test VM was corrupt. No idea how it had happened but I decided to test my utils out.
In doing so, I ran e2fsck -n /dev/mapper/vgsystem-lvvar and it created a whole slew of error messages. Zero inodes, bad dates, orphaned inodes, etc. So I let e2fsck fix them using e2fsck -y /dev/mapper/vgsystem-lvvar... One of the things I saw run by me was "...erasing journal... device is now ext2" or something. <enter panic mode> thankfully Mandriva has a good Emergency Recovery section. It pointed me to some useful utilities.
If you have a bad superblock, try the switch for e2fsck -b 8193 first. There may be a perfectly good backup available. When you delete the ext3 journal, tune2fs -j device recreates it for you and rescuept can scan bad partitions for try to make sense of them...
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