Each raid set can have only one physical drive size in it. As you see on
yours the 074s show up as 'smaller' due to the parity strip being on
those drives while the 070s show up as full capacity. In any case when
you create a RAID5 set you lose one physical drive worth of capacity to
the parity data. (Aside: With RAID6 you lose two)
Yes in theory your set is a bit skewed in that only 4 drives have
stripes while the others are all 'klingons'. The protection is not
compromised but performance might be - a little and then mostly if one
drive is currently failed.
That RAID card can have four RAID sets I believe (memory) so no issue
there. Neither the controller nor the O/S will care about the 70/140/280
thing they just do their jobs. However performance can suffer when the
280s are tasked with four times the workload of the 70s. If your drives
are 2 to 5% busy today it might not matter to you. If they are
constantly in double digits then you're going to care. Worst I ever saw
was 2, 4, 8, 17, and 35GB Drives in the same ASP. The 35s took it on the
chin and then when a cache battery checked out (care to guess which RAID
set was affected??? :-) ) it got ugly bad.
On 9/4/2012 10:57 AM, rob@xxxxxxxxx wrote:
Can I have multiple size drives in one raid set? Or should I start
another raid set? If I can have them all in one raid set should I
end/restart raid on this set anyway to further spread the stripe?
I take it multiple size drives in the same 5787 is not a problem?
I'm still mulling over your other comments about the 70/140/280.