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nownot
Aug 26, 2009, 02:17 PM
Does (or will) Leopard or Snow Leopard server have the ability to do software raid 5? So if I install either on my mac pro and fill sata ports w/ 1 tb hd's will I be able to create a software raid 5, thanks for any input.



belvdr
Aug 26, 2009, 02:20 PM
It doesn't look like it. (http://www.apple.com/server/macosx/technology/file-system.html) However RAID 10 is available and a good choice.

uberamd
Aug 26, 2009, 02:23 PM
I've never liked software raid to be honest. As I type this my XServe RAID is creating a 2TB hardware RAID 5 array :)

belvdr
Aug 26, 2009, 02:24 PM
I've never liked software raid to be honest.

Me either.

As I type this my XServe RAID is creating a 2TB hardware RAID 5 array :)

That's it?

nownot
Aug 26, 2009, 02:41 PM
correct me if I'm wrong but with raid 10 you loose the space of half of the hd's where as with raid 5 you loose 1 ...... right?

belvdr
Aug 26, 2009, 02:54 PM
correct me if I'm wrong but with raid 10 you loose the space of half of the hd's where as with raid 5 you loose 1 ...... right?

Correct, but where RAID 5 lacks in writing, RAID 10 shines. Additionally RAID 10 has much less overhead than RAID 5, as no parity needs to be calculated.

nownot
Aug 26, 2009, 02:57 PM
Correct, but where RAID 5 lacks in writing, RAID 10 shines. Additionally RAID 10 has much less overhead than RAID 5, as no parity needs to be calculated.

true but
6 x 1.5 tb raid 5 = 7.5 tb :D
6 x 1.5 tb raid 10 = 4.5 tb :mad:

kinda hurts :P

belvdr
Aug 26, 2009, 03:43 PM
true but
6 x 1.5 tb raid 5 = 7.5 tb :D
6 x 1.5 tb raid 10 = 4.5 tb :mad:

kinda hurts :P

true but
6 x 1.5 tb slow raid 5 = 7.5 tb :mad:
6 x 1.5 tb fast raid 10 = 4.5 tb :D

:) Seriously though, on a software RAID, RAID 5 tends to chew up some CPU, whereas RAID 10 does not. It's all in what you need, but if you need RAID 5, you'll need a hardware array controller.

snakesqzns
Sep 1, 2009, 09:08 PM
Is ZFS an option? If so that'd be better than RAID 5 (on paper, I don't know the status of the mac ZFS implementation)