Comments on: Multiple RAIDs on a common set of drives http://storageadvisors.adaptec.com/2006/11/16/multiple-raids-on-a-common-set-of-drives/ Storage Solutions for Real World IT Professionals Fri, 19 Mar 2010 18:40:58 +0000 http://wordpress.org/?v=1.5.2 Comment on Multiple RAIDs on a common set of drives by: Tom http://storageadvisors.adaptec.com/2006/11/16/multiple-raids-on-a-common-set-of-drives/#comment-19508 Wed, 22 Nov 2006 12:31:37 +0000 http://storageadvisors.adaptec.com/2006/11/16/multiple-raids-on-a-common-set-of-drives/#comment-19508 First, are those drives qualified to run with a RAID card, i.e., do they have a reduced error timeout? I think the answer is "yes". I couldn't find anything on the WD website about this, but the drives are certainly positioned as "enterprise". (If they didn't have the reduced error timeout, and you absolutely had to use these drives, then I would have said RAID-6.) So what would I personally do? I would build a RAID-5. Capacity will be 50% better than a RAID-10, and I'm always running out of space - especially since these drives are relatively small. You said you only need 60GB, and RAID-10 will give you 72GB and RAID-5 will give you 108GB. If you absolutely want the best write performance, then I'd go with RAID-10. But I'm willing to sacrifice a little write performance for the extra capacity of RAID-5. Next, I would use hardware RAID because (a) I want to use write-back cache (especially since it's RAID-5) and therefore I need a battery, and (b) I don't trust software RAID. Lastly, even though I hate to talk about specific products, but because you're both persistent and patient :-), I would use an Adaptec 4805SAS hardware RAID card (which of course also supports SATA). TT First, are those drives qualified to run with a RAID card, i.e., do they have a reduced error timeout? I think the answer is “yes”. I couldn’t find anything on the WD website about this, but the drives are certainly positioned as “enterprise”. (If they didn’t have the reduced error timeout, and you absolutely had to use these drives, then I would have said RAID-6.)

So what would I personally do? I would build a RAID-5. Capacity will be 50% better than a RAID-10, and I’m always running out of space - especially since these drives are relatively small. You said you only need 60GB, and RAID-10 will give you 72GB and RAID-5 will give you 108GB. If you absolutely want the best write performance, then I’d go with RAID-10. But I’m willing to sacrifice a little write performance for the extra capacity of RAID-5.

Next, I would use hardware RAID because (a) I want to use write-back cache (especially since it’s RAID-5) and therefore I need a battery, and (b) I don’t trust software RAID.

Lastly, even though I hate to talk about specific products, but because you’re both persistent and patient :-) , I would use an Adaptec 4805SAS hardware RAID card (which of course also supports SATA).

TT

]]> Comment on Multiple RAIDs on a common set of drives by: Bill http://storageadvisors.adaptec.com/2006/11/16/multiple-raids-on-a-common-set-of-drives/#comment-19417 Tue, 21 Nov 2006 21:06:26 +0000 http://storageadvisors.adaptec.com/2006/11/16/multiple-raids-on-a-common-set-of-drives/#comment-19417 Great stuff for sure! Thanks. Let me ask this another way. If you were to build your ultimate workstation (internet development mostly [lots of mass search and replaces in Dreamweaver], PhotoShop/ImageReady, no games), already had 4 36gb 10k Raptor drives (could buy more) and was looking for high performance in your next machine, what would you do? A loss of data would be bad for you. You needed at least 60 GB drive space. Cost not a real concern. What RAID level(s) would you use? Would you use a third-party card? I'm going to put you on the spot and ask you to name names (manufactures and p/n's) Great stuff for sure! Thanks.

Let me ask this another way. If you were to build your ultimate workstation (internet development mostly [lots of mass search and replaces in Dreamweaver], PhotoShop/ImageReady, no games), already had 4 36gb 10k Raptor drives (could buy more) and was looking for high performance in your next machine, what would you do? A loss of data would be bad for you. You needed at least 60 GB drive space. Cost not a real concern. What RAID level(s) would you use? Would you use a third-party card? I’m going to put you on the spot and ask you to name names (manufactures and p/n’s)

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