question on vinum

[secmgr]

Chuck Swiger wrote:

> No.  All of the drives need to be the same size.  With RAID-5, which 
> drive is used to hold parity data rotates on a stripe-by-stripe basis 
> to balance out the load.

Just to clarify this point.  All the subdisks in the plex need to be the 
same size.  The physical drives and even the bsd partitions/vinum drives 
do not actually have to be the same.

An example would be you have 2x 40gig partitions, and 2x 60 gig 
partitions.  You could make a stripe set using 4 40gig (160gig) subdisks 
(or a 120gig raid 5 set). You just would't use the remaining 20 gig on 
the other two drives.  You could use the space, just not for this plex. 
(you could create a 40gig (20+20) stripe or concat set or a mirrored 
20gig area) Concat, on the other hand doesn't care and would happily use 
40+40+60+60 (just not with the same perf levels)

jim