Questions about RAID requirements

[CompGeek]

Im thinking about setting up RAID, need to know the basics.

Do the HDDs have to be identical? Just the same size? Just the same size+rpm+cache?

Western Digital makes both SE and RE drives, can I still use the SEs in RAID? Can I pair an 200GB 7200RPM HDD with my current Western Digital 200GB Caviar SE in RAID?

Appreciate the help guys. :toast:

[uOpt]

Depends, depends, depends.

Depending on how flexible you software is they don't even have to have the same size. In my Linux software RAID for example I don't raid disks, I raid partitions. So I can have two 200 and one 250 and make a three-disk raid with 3x 200 GB and have a plain 50 GB partition. It doesn't care about speed or cache either, although of course it screws up the performance optimizations if the drives are different speed.

Hardware RAID controllers might be more picky.

I wouldn't use than onboard sata RAID trash for anything redundant, just raid-0.

In my opinion, these WD drives are a scam. I think WD is patching up very serious firmware problems in their "Raid editions". I don't recommend either WD line for use with anything. WD has a long history of destroying data with broken firmware (although I have to admit that they seem to be mechanically well-built and don't physically die easily).

[CompGeek]

Well, I have no choice but to use WD as both of my drives are WD (a 250g and a 200g)

I'll be using my onboard RAID controller on the bad axe, and then later on porbably an nForce 590 RAID controller.

[Vric]

You will most likely be able to use those 2 drive, even if they aren't the same capacity. you will loose the 50gb of the 250gb, but beside that it should work.

I'm going on memory, but the RE edition of WD have no CRC check on the disk. They rely on the Raid controller to do it. It help a bit for performance, but it also help to solve some bug when under heavy load, the HD would stop responding for few second and the Raid controller would declare it "dead". In Raid1/5, it would have to rebuild the drive, but on Raid0, it would be data lost. But it happen rarely. (if any)

The most important thing is: Don't use the RE edition drive without using a raid controller. You will end up with many CRC error and data lost.

[CompGeek]

well, i was going to buy either a 250GB or 200GB to match one of my current drives :)

Thank you for the help.