Raid questions

[Joker1]

Ok here it goes;

I'm finaly getting around to my mega upgrade and ive decided to get the KT7A-Raid from abit. I'm planning on thorwing two seagate 7200rpm 30 gig drives on it. Now here's where it gets tricky. I would like to make one partition on each drive thats say 8 gigs then set them up in Raid-0 (stripe) while taking the rest of the drive space and setting it up in Raid-1 (mirror). Ideally i'd want to end up with a ultra fast drive and an ultra reliable drive. One for OS one for MP3s, Documents and legitimate backups of course. Is there a way to do this or am i smoking to much crack?

Note: i know next to didly about raid so if i got the types wrong just let me know.

Also if you guys know of a better HD i can get for 199CAN$ let me know as for the board i'm pretty hard set on it and yes i know about the Udma100 south bridge issues.

[Shades]

Hello there - maybe you are smoking too much crack (lol j/k).

No, you can only have one type of raid for one particular disk (as far as I know). The minimum number of disks for raid 0, raid 1, raid 0+1 is two. Therefore, going on that basis, your configuration can only be either a raid 0 for both drives, or raid 1 for both drives or raid 0+1 for both drives.

In your situation you won't be able to have mixed configuration on the same two drives. It also goes for raid systems that the disks in the array MUST be of identical size. ie in your case 2x30GB.

Hope you can understand this - but I guess the straight answer to your question is no, you can't do the mixed configuration you want to do. Have either of the configurations, but not both. Cheers.

[Joker1]

thats what i suspected
dang, would have been nice to get the best of both.

One other thing, doesn't raid0+1 require four drives so it can be mirrored and striped.

[Fubarian]

yes, you need 4 to do the mirror/stripe deal.

I'm still testing a theory, but I haven't confirmed it yet, but from my 1st benchmarks, -mirroring- will give you more xfer rates than stripe. Why?...I'm assuming its the overhead, the stripe has to be checked, a mirror doesn't. 1st few benchmarks I was getting 170 megs/sec (2 drivers, 15.3 gig maxtors, 5400rpm and 512k cache, udma 100) and with stripe, I was getting around 65. Again, it might vary with bigger / faster spin / more cache drives... for the record, I was using a benchmark utility called Atto.

[Joker1]

Originally posted by Fubarian:
yes, you need 4 to do the mirror/stripe deal.

I'm still testing a theory, but I haven't confirmed it yet, but from my 1st benchmarks, -mirroring- will give you more xfer rates than stripe. Why?...I'm assuming its the overhead, the stripe has to be checked, a mirror doesn't. 1st few benchmarks I was getting 170 megs/sec (2 drivers, 15.3 gig maxtors, 5400rpm and 512k cache, udma 100) and with stripe, I was getting around 65. Again, it might vary with bigger / faster spin / more cache drives... for the record, I was using a benchmark utility called Atto.

What board were you using to create the array?

[n8dawg]

Originally posted by Shades:
In your situation you won't be able to have mixed configuration on the same two drives. It also goes for raid systems that the disks in the array MUST be of identical size. ie in your case 2x30GB.

correct they need to be the identical size BUT you can have a 10 drive and a 20 gige drive partion the 20 gig into 2 partions that would give you 3 10 gig drives and stripe all drives you could even do parity at this point (usless but can be done)
i think that this configureation is possable but dont understand why you would do it like that with mirror you are going to lose at least half your drive and striping isnt fault tolerant. I think it can be done but i dont see it resonable