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RAID levels, do you care about your data?

So I thought this was an interesting exchange on SpiceWorks. http://community.spiceworks.com/topic/95946

Basically it questions the use of RAID 5 (or 50 in a production environment) this would apply whether you had an EqualLogic or any other SAN I would think?

Basically RAID 5 has a flaw called the

RAID-5 write hole. Whenever you update the data in a RAID stripe you must also update the parity, so that all disks XOR to zero — it’s that equation that allows you to reconstruct data when a disk fails. The problem is that there’s no way to update two or more disks atomically, so RAID stripes can become damaged during a crash or power outage.

http://blogs.sun.com/bonwick/entry/raid_z

I guess the question is, is it appropriate to have a production SQL or Exchange server running on a RAID 5 (or 50??) volume? Mr. Scott Alan Miller would I think say no. He likes RAID 10 for that sort of thing.

Any thoughts?

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