Superblock missing, FS corruption after power outage
rdavidson at bdi.org.au
Tue Apr 21 09:17:24 UTC 2009
I'm wondering if its possible that an ext3 filesystem with journaling enabled
and so on (defaults really) could lose its primary superblock and lose, in
this case, a whole directory which contained a virtual server.
It is possible in this case that a fair chunk of data could have been lost as
the RAID card has a 256mb cache with no battery backup for cached data, but it
seems somewhat extreme that the superblock went missing (according to mount
the filesystem didn't exist, according to fsck.ext3 it had to use a backup
superblock), and that a whole directory disappeared and didn't end up in
During the fsck there were lots of claims of inodes claiming the same data
blocks as some other inodes and as such the fsck chose to clone those blocks.
In some instances - well, at least one, a directory that contained PostgreSQL
databses became a symbolic link to some python file after the fsck.
So I'd like to know if all of this is possible just from a power failure, or
if there is something else going on that was possibly causing file system
corruption that wasn't noticed until the reboot.
More information about the Ext3-users