Update on the PERC situation

Followup up on the PERC fiasco. After a few more back and forths with DELL, the following facts have become clear :- If you’re using a PERC with a direct attached JBOD (eg. MD1000) any discontinuity will result in the card reporting a foreign configuration error and you’ll have to reimport the configuration and let the drives do a full background ‘initialization’ (which really means verification in this context).

  • If you’re using a PERC with a direct attached Powervault solution (eg. MD3000) discontinuities will be automatically handled by the internal RAID card in the MD3000 so that the foreign configuration issue will not require manual intervention. Now obviously, if you lose power to an MD3000, the controllers and the disks go down at the same time so theoretically it should come back up directly.

What’s still not clear:

  • Still no confirmed answer on how the MD3000 handles a missing MD1000 disk bay when used as a SAS extension. The basic response is that it will not require any user intervention (good), but it remains to be seen whether or not this situation provokes the background initialization or not (potentially bad).