Can anyone give me a brief overview of hardware vs. software raid. We are looking at doing a simple mirror in NT4 server do we need a $600 controller to do this? Ray

No, you need 2 hard drives to do this. It's better to do it with a raid controller, but if you dont have it, just do it in NT Disk Administration menu. Software will let you create a mirror on one hard drive, 2 partitions, and if the hard drive fails, you are toast. But hardware controller requires 2 phisical hard drives.

Follow this link: http://www.finitesystems.com/PRODUCT/raid/raidlevel.htm It provides a more than brief, but well written overview of the various flavors (levels) of RAID. I recommend RAID 1, hardware solution. Uses lots of storage space, but it's fast and very stable. Not cheap. Digi and Adaptec are at the head of the class in this technology.