I have successfully installed CentOS 5.1 x64 on a system with a mirrored RAID. The system board is an Intel S5000XVN and an integrated RAID controller. Both disks are 500GB SATA drives. I was testing the RAID functionality earlier and discovered that the mirror is not working as I previously thought.

When I removed drive 0 from the mirror, the system booted as I expected. The RAID was degraded but my data was intact. I shutdown the system, inserted drive 0, removed drive 1 and rebooted the system. Again, the RAID was degraded, but when the system booted, none of my data was there. It's like I was writing to one of the two mirrored drives.

I've also noticed that on boot, I get the following error:

failed to stat () /dev/mapper/ddf1_4c53492020202020808626820000000036b9858700000a28

I don't know if this is related or not.

Also, dmraid -s reports the following:

# dmraid -s
*** Group superset .ddf1_disks
--> Subset
name : ddf1_4c53492020202020808626820000000036b9858700000a28
size : 974608384
stride : 128
type : mirror
status : ok
subsets: 0
devs : 2
spares : 0

Thoughts on what might be going on here. Thanks.