Re: AIX: mirrored drives and Oracle corruption

Ensure that the sysadmin has quorum for the vg turned off. We've lost drives on several occasions and not had a problem. But if quorum is active, and there are only 2 drives in the vg, AIX will vary off the volume group when the disk fails, and Oracle will eat it, probably corrupting your data in the crunch because it's writing to the lv's in the vg.

Once quorum is on, a disk can fail, and the lv's on it will go stale. AIX logs disk errors, but to my knowledge won't specifically notify you that an lv has been marked stale. It's up to the sysadmin to clue in that with disk errors (they will continue to happen hourly), he should be invigilating the lv's.

Then, he will unmirror the lv's, reducevg the disk out of the volume group, replace it, extendvg the new disk into the volume group, and remirror the lv's or entire volume group.

Steve Perry wrote:
>
> Hi Norman,
>
> I didn't state it clearly. One of the drives fail, Oracle chokes, AIX doesn't
> know, shutdown the db, sys admin replaced the drive, we had to recover the files
> on the mirrored drive. The other half of the mirror was fine. Oracle sensed the
> problem, but AIX didn't.
> I would have thought AIX would have noticed it and an alert would have been sent
> to the SA. They would have notified us and scheduled maintenance to replace it.
>
> Thanks,
> Steve
>
> Norman Levin wrote:
>
> > Removing a drive in aix is NOT the same as removing a drive in Sun. It
> > wouldn't
> > surprise me if the device was not removed from the volume group before it was
> > physically removed. A 'rmdev -l disk# -d" is NOT the clean way to remove a
> > disk.
> > --
> > Norman Levin
> > vm/dynAmIX inc.
Received on Tue Aug 10 1999 - 17:01:00 CDT