6x36G drives in a RAID5 config == ?

[Kenneth D. Merry]

On Fri, Aug 06, 2004 at 18:56:26 -0300, Marc G. Fournier wrote:
> 
> I have a server with 6x36g drives in her, hanging off an Intel RAID 
> controller, so that I can access it from FreeBSD using storcon ...
> 
> According to StorCon:
> 
> The drives are all Capacity 34971MB ... 'Configure Array Drive' says that 
> Capacity s 139884MB ... Shouldn't capacity be closer to 174855MB if all 
> drives are used as part of the Array?  Am I right that the 6th drive is 
> 'the hot spare' in this case?

It probably is, unless they're using a "built in spare" or something like
that.  (If you reduce the capacity used on each drive by
drivecapacity / (N - 1), where N is the number of drives in the array (in
this case 6), you could probably use the leftover space on the remaining
drives to reconstruct onto instead of reconstructing onto a spare drive.
The only thing that would really buy you would be that you would be
exercising your spare drive, and you'd have an extra spindle.  Probably not
generally worth it.)

In any case, you should be able to figure out from the utility or the BIOS
which drive is the spare.

Ken
-- 
Kenneth Merry
ken at kdm.org