Re: ext3 filesystem is not recognized after losetup -e aes

[Dennison Williams <evoltech@2inches.com>]

Dennison Williams wrote:
> Here is the setup: MD software RAID 5 on 4 disks (md0), a LVM logical
> volume (/dev/volume_group/logical_volume) comprised of one physical
> device (/dev/md0), a encryption layer provided by the cryptoloop driver
> (losetup -e aes /dev/loop0 /dev/volume_group/logical_volume), then a
> EXT3 file system (mkfs.ext3 /dev/loop0).
> 
> Recently the RAID device kicked out one of the disks during a large file
> transfer. After re-adding the disk to the array whith "mdadm /dev/mdo
> -add /dev/sde (smartctl didn't report
> anything wrong with it, I am not sure why this happened), authenticating
> against the cryptographic layer, then trying to mount the drive, I get
> the following error:
> 
> [root@storage redhat]# mount -t ext3 /dev/loop1 /terrorbyte/1/
> mount: wrong fs type, bad option, bad superblock on /dev/loop1,
> 
> The message in /var/log/message is:
> VFS: Can't find ext3 filesystem on dev loop1.


I saw in the encryption howto, section 6.1, talks about the effects of
blocks occupying different space when the kernel is compiled with the
CONFIG_BLK_LOOP_DEV_USE_REL_BLOCK option.  Would this effect also be
possible by a RAID5 system re-syncing a drive?  I don't see this
configuration option anywhere in the 2.6.18 kernel (I am using a redhat
build of this kernel).