Reminder -- RAID 5 is not your friend

[kentborg-KwkGvOEf1og at public.gmane.org (Kent Borg)]

Richard Pieri wrote:
> And neither is RAID 1.  Except when you get lucky.
>
> I had a failure over the weekend.  Two mirrored pairs, A1/A2 B1/B2 configuration.  A2 and B1 failed simultaneously.

Sounds like it is *disks* that are not your friend. And, that they hate
you enough that your use of raid isn't enough to save you.

My conclusions:

1. don't run matched disks from the same manufacturer and lot
2. watch disk temperature
3. watch smartmon for indications of aging
4. replace disks before they die
5. use your replacements as an opportunity to get your pairs staggered
6. have backups that at minimum are ping-ponged, current, and physically
offline
7. goto #1...


-kb