RAID 0+1 and RAID 1+0

This is from an article by Kim Tripp from Saturday, May 13th. I'm reprinting part of it here for all of our SQL DBA's.

RAID 0+1 and RAID 1+0
"There was a question that came up on this and the question basically asked - which is better. Well, this is a hard question to answer because they both have pro's and con's BUT before I get to the pro's/con's there's also another [more important] issue; these two get confused and swapped all the time. In fact, many vendors USED to refer to these interchangeably and even just lumped them together as RAID 10. Today, most people don't do this and most people also try to refer to the underlying technlogy instead of the numbers. Having said all of that, RAID 1+0 is Striped Mirrors and is my general recommendation because it tends to be more reliable than 0+1 and can tolerate more drive failures than 0+1. RAID 0+1 is Mirrored Stripes - which generally outperforms RAID 1+0 but cannot tolerate the loss of more than one drive and because of that it's more vulnerable. In the end, I'd suggest a simple "educational" site here (it's on a commercial site but it has a nice - and short - description of the different types of RAID arrays). "

The whole thing is here and you can find Kim's blog here along with SQL tips and webcasts. Kim's my favorite SQL trainer. She's full of energy and really bright so spend some time on her sight. (I apologize for that last line but I couldn't resist.)