SQL Quiz 5: SANs Mirroring

August 12, 2009 at 8:05 am (SQL Server 2005, SQL Server 2008, SQLServerPedia Syndication) (, , )

My turn to answer Chris Shaw’s questions “Do I feel I have a reliable SAN solution?” and “Describe Database Mirroring for the layman?” Thanks Tim. I’ve a feeling you’re going to be disappointed.

Hell, how should I know? Want to talk about a black box? Our SAN, as far as I’m aware, is run by a group of crack-shot ninja assassins and powered by pureed virgin unicorn. This strange mix of esoteric skill, magic and blood is evidently able to provide us with just about perfect up time. Once, one of the ninja’s must have gone rogue (speculation) and had to be put down by his brother ninjas because we had a drive disappear on the cluster server. It took us a couple of hours, but it recovered as if it was never gone.

Honestly, I just don’t know. We’ve done performance tests and we’re getting more than adequate I/O. I know that we don’t have all kinds of specialized luns catering to the tempdb or log files. Instead we have what appear to be drives that we can use for storing data. It just works. Our team has tried communicating with the ninjas, uh, I mean SAN administrators, but they kind of just nod their heads, ask us how much space we need, and suppy us with another drive. 

I’m not sure how I’d describe this to the layman. I’d say it’s like a stand-by pump, but automatic. If the main pump goes down, the valves automatically switch and the stand-by pump comes online. Our business people have learned what fail-over clusters work like. I could tell them that it’s like a fail-over cluster, but without the shared drives, which makes it safer in a lot of ways. However, beyond reading about mirroring, I have yet to implement it, so it’s all theory for me.

So to sum up, the answer to both questions is, I don’t know. Pretty pathetic, but honest.

Let’s tag… Tim Mitchell & T-Jay Belt. Those guys should have more going on than I do.


  1. Weekly Links for August 14 | Brent Ozar - SQL Server DBA said,

    […] I made some jokes in my response and things went swiftly downhill from there.  See answers from Grant Fritchey, Jason Massie, Tim Ford, Tom LaRock, and […]

  2. Mark said,

    I’d say it’s like a stand-by pump, but automatic…

    Love the description! i think I’m going to ‘borrow’ it for conversations about DR…

  3. scarydba said,

    Holy cow! I wrote something useful? I’m so sorry. I’ll try to make sure it never happens again.


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