building a raid ? use drive from different batches

Having been away from the computer for most of the day, when I got a chance to check email in the evening, there were a few frantic emails from a friend of mine having lost complete access to a raid set. Now, I've just spent a few hours, recovering and rebuilding that raid for him. In all he had 4 drives fail. Together.

One of the basic rules of building a raid set is that you try and vary the model / batch / make of the drives ( within reason ). Because most drives from the same batch can fail at the same time. And they do. Drives out of the same batch, running in exactly the same role, under the same conditions and with an identical data load. You do the math.

So next time you need a bunch of drives in a machine, make sure they dont all come from the same batch, and you will have a much higher chance of loosing only 1 drive at a time ( and lets face it, drives fail sometime or the other. )

--
Karanbir Singh { http://www.karan.org/ }