data parity drive without RAID?

hey, all,

I'd set up a RAID 5 array, but construction and expansion would be tough.

Basically, what I want is parity for 2 250 GB HDs, but more later. I want to do it without mirroring all that friggin' data. RAID 5 would be great even though I don't need any performance boost. However, setting up a raid 5 array would require formatting of the 2 drives, the additional drive for parity sharing, and no ability to add more drives into the array later.
If I want a larger array, I'd have to reformat. Each formattting would require backing up the ultra-gigs of data elsewhere (I don't know where that could possibly be!).

So, I looking for some program/controller that will give me data parity and expandability.

Anybody know of such a thing?

No controller would give you expandability I don't think. You'd want to look into Volume Management for that. I don't know how versatile Windows' is, haven't really fooled with it. I've done it with Linux - had a jbod that I could add a disk to whenever I felt like it and expand onto that disk without reformating or unmounting. Not sure how to integrate that with a raid5 though.. the parity data is dependent on the size of the array.

Its raid3 which has a dedicated parity drive, isn't it?

I suppose that if Windows 2000's volume management was as good as Linux's is, you could have multiple underlying raid5s or mirrors or whatever, and at the level above that you bring them all together with a jbod, and then you format that jbod with your filesystem and grow it as you add more disks or raids. So the underlying data is guarded, although it doesn't represent the direct filesystem information, and if a disk dies you'll have to deal with it at the raid level and get that sorted out before the jbod would be usable again. Sounds practical enough, I'd do it if I had requirements and resources like yours I think.