RAID with different-sized drives

[jong2k4]

I'm planning on installing a RAID card on a computer at work for which data integrity is essential. The computer already has two hard drives and more than enough leftover space to have one drive mirror the other. They are Western Digital 40 and 60 GB Caviar drives. I'm planning on just using RAID 1. From what I've heard, it is possible to use RAID 1 with different-sized drives, but it will be limited to the size of the smallest drive, which is quite all right with me. I just wanted to check and see that it was in fact all right to do this.

I was planning on using this card ; this is a moderately expensive card considering others were under $20 and this is $47, but I felt uncomfortable going with a cheaper card when the whole point of this exercise is to ensure that the data is very well protected, and espcially considering the unique budgeting nature of academic labs (ie once a grant is about to expire, do a mad dash to spend all of the money left on it.) Still, if anybody thinks a cheap RAID card is more than sufficient, I'd rather save a bit of money.

Also, is there anything else I should know before setting up a RAID? If this is a success, we will probably be installing more arrays.

[Force Flow]

You're better off with the capacity rather than doing RAID. Outside of server envronments, RAID does not offer much other than the increased risk of data loss. Two HDDs linked together means you'll have twice the chance of losing your data--even with mirroring! If the primary drive goes in a mirrored setup, the controller often tries to mirror the dead or dieing drive and ends up losing all the data anyway.

You're better off either backing up your files to the other drive or performing a regular disk clone as a backup.

And if the data is *that* important, you may want to think about backing up to a portable external drive too.