[CentOS] 3ware disk failure -> hang

Fri Jan 6 20:11:01 UTC 2006
David Thompson <thomas at cs.wisc.edu>

"Bryan J. Smith" wrote:
>
>Had you used the 3Ware's intelligent hardware RAID, it would
>have hidden the drive disconnect from the system.  You'd see
>a log entry on the failure, and that the array was in a
>"downgraded" state.
>
>Instead, you're using software RAID, and it's up to the
>kernel to not panic on itself because a disk is no longer
>available.  The problem isn't the 3Ware controller, it's the
>software RAID logic in the kernel.

<smile>As much as I hate to agree with Bryan </smile>, this has been our 
experience also.  We have many TB of disk running with 3ware controllers.  We 
used to use software RAID, because at that time we found 3ware's tools to 
notify us of disk/array problems unusable.  During that time, we could always 
tell when a disk failed, because we would have a crashed server.  The data 
would always be there after we rebooted, but a reboot was necessary.  A few 
years ago we migrated everything to 3ware hardware RAID, and now we rely on 
our alert system, instead of our users, to tell us when a drive fails.

Dave Thompson
The University of Wisconsin - Madison