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Re: Unload/Reload



fixed

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.

- DrF

On 9/4/2012 10:57 AM, rob@xxxxxxxxx wrote:
Thank you.
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.


Rob Berendt






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