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View Full Version : Raid 5 Question here..


saweetnesstrev
09-30-05, 02:07 AM
How many hard drives does it take to get raid 5 ,, 2-4?? hopefully 2 ,, thinking about buying this mobo.. http://www.tweaktown.com/document.php?dType=article&dId=813&dPage=2

jAkUp
09-30-05, 02:15 AM
For RAID 5 I believe you need 3 or more drives. 2 for the stripe, one for the redundancy.. or more. :)

seeker010
09-30-05, 02:26 AM
For RAID 5 I believe you need 3 or more drives. 2 for the stripe, one for the redundancy.. or more. :)
you mean 2 or more for stripe, 1 for redundancy ;)

jAkUp
09-30-05, 02:30 AM
yea, 2 or more for the stripe, one for redundancy...

hmmm, can you have 2 drives on a stripe, and 2 more drives on a stripe for redundancy?

Sounds kinda useless, but I was just curious :) heh

superklye
09-30-05, 02:31 AM
i think it goes:
2/1: stripe/redundancy
3/1: s/r
4/2: s/r

But I don't know for sure.

saweetnesstrev
09-30-05, 02:44 AM
Thanks :)

superklye
09-30-05, 02:47 AM
This is from my new Gigabyte K8N Ultra SLI mobo manual:

Parity RAID (RAID 5)
Parity or RAID 5 add dault taolerance to disk striping by including parity information with the data. Pairty RAID dedicates the equivalent of one for storing parity stripes. The data and parity information is arranged on the disk array so that the parity is written to different disks. There are at least 3 memebers to a Parity RAID set.

parity RAID uses less capacity for protection and is teh preferred method to reduce teh cost per MB for larger installations. Mirroring requires 100% increase in capacity to preotect the data wheras the above only requires a 50% increase. The required capacity decraesaes as the number od disks in the group increases.

saweetnesstrev
09-30-05, 02:51 AM
Thanks superkyle

superklye
09-30-05, 02:55 AM
Sure thing man. Sorry I don't have more concrete info for you, but it looks like as long as your parity is at least 50% (and maybe even less), you'll be good to go. :)

dandano
09-30-05, 01:43 PM
It's always only one drive for parity checking. I have a 6x120GB hd raid5 here at work, and only one is used for parity.

Btw, raid5 is not really great performance, but it is the most economical form of raid.

danh

superklye
09-30-05, 02:10 PM
Oh, that's cool...thanks for the info, danh. :)

Strahd
09-30-05, 03:08 PM
The minimum hard drives for raid 5 is 3 :)

seeker010
09-30-05, 06:54 PM
yea, 2 or more for the stripe, one for redundancy...

hmmm, can you have 2 drives on a stripe, and 2 more drives on a stripe for redundancy?

Sounds kinda useless, but I was just curious :) heh
I'm not quite sure what you're asking. You can have raid 50 which is what I think you might be saying? http://www.pcguide.com/ref/hdd/perf/raid/levels/multLevel05-c.html
there's also raid 6 which is raid 5 with 1 extra redundancy disk. and then raid 10 and 0+1....