RAID 0 is striping. No fault tolerance.
RAID 1 is mirroring/duplexing and some fault tolerance.
The Dell server should almost certainly be able to mirror, but I dunno what would be required (presumably for safety-sake one would want a full backup first).
He is intending to increase drive size by removing 160GB disks, one at a time, and replacing them with hot swap 1TB drives. I'm having my doubts and am trying to get him to back everything up with redundancy. I figure worst case, he can replace all disks, reformat, and reload from backup.
I think you're right to be worried. There's a chance that the BIOS/Windows SP level may not understand 1TB disks. There is a 128 GB (48-bit LBA) barrier, which Win2k3 presumably crosses given the 160GB drives, but there may be issues with the larger drives as well. Don't assume everything is just plug-and-play with something critical like this.
MS on RAID 0 on Win2k3 - http://support.microsoft.com/kb/323433 Note that the drives are "Dynamic Disks". These are different from standard "Basic" partitions that you can transfer easily between machines, etc. The hardware RAID via the controller may have different capabilities.
Troubleshooting
* Do not mix hardware RAID 0 with software RAID 0.
* A striped volume cannot hold the system or boot partition of a Windows Server 2003-based system.
* You cannot extend or mirror striped volumes.
* There is no fault tolerance on a striped volume. This means that if one of the disks becomes damaged or no longer functions properly, the whole volume is lost.
It may ultimately be faster to do a full backup, install the new drives, build the desired array, then restore the backup than to have the RAID rebuild via sequential installation of new drives (which the MS link seems to say is not possible anyway. However, the add-on controller may be able to do it). (Rebuilding stripes with separate parity drives can take forever, IIRC.)
But, I'm no expert - just passing along stuff I've read.
HTH. Good luck!
Cheers,
Scott.
(Who is probably going to order one of these in a few weeks - http://www.amazon.co...8&m=ATVPDKIKX0DER - and make a RAID 5 array with 4 ea 1.5 TB drives.)