RAID-5 and database servers

Jefferson Ogata poweredge at
Thu Mar 11 16:29:21 CST 2010

On 2010-03-11 22:23, Matthew Geier wrote:
> I've had a disk fail in such a way on a SCSI array that all disks on 
> that SCSI bus became unavailable simultaneously. When half the disks 
> dropped of the array at the same time, it gave up and corrupted the RAID 
> 5 meta data so that even after removing the offending drive, the array 
> didn't recover.

In that scenario you *should* be able to recover by reconfiguring the 
RAID as it originally was before the SCSI crash, and *not* initializing 
the logical drives.

I have my systems all mail me a nightly report of RAID configuration in 
case I ever need to do this. While I might be able to remember how I 
configured RAIDs at install time, the config may change over time, e.g. 
after a hot spare is brought online.

If you are using LSI-based RAID controllers, you might be able to save 
the current controller config with MegaCLI using the -cfgsave option 
periodically, and recover the config after a crash using -cfgrestore.

More information about the Linux-PowerEdge mailing list