First off, to amplify a bit on what Andy said, I would NEVER place a database file on NAS. If you are looking for SQL Server storage definately look at SAN not NAS.
The only problem with SAN's is the expense, those with penny pinching CFO's beware! Also, not all SAN's are created equal. Our first SAN's were Xiotech. After several years of using them and suffering several incidents of data loss, we kicked them to the curb and went with EMC. We not only improved our reliability, but our I/O performance increased between 25%-30%! As I said before, it isn't cheap though, we price out our storage costs internally at $220 per Gigabyte! That figure includes the Fibre Channel cards, cabling, storage, administration, and backup.
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If most people are not willing to see the difficulty, this is mainly because, consciously or unconsciously, they assume that it will be they who will settle these questions for the others, and because they are convinced of their own capacity to do this. -Friedrich August von Hayek
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