power outage. corrupted superblock and group descriptor on db server root file system. tried "mke2fs -n /dev/sda1" e2fsck with an alternate superblock didn't work. looked at "dumpe2fs /dev/sda1|more"...
This worth a try:
dd if=/dev/sda1 of=/data/sda1.bak.dd
mke2fs -S /dev/sda1
reading RedHat ext3 mailing list archive
also how to make customized bootable CD from running system?