Raid 5

mattyj1085 · 16 Sep 2009 at 15:51

Do I have to have all the same drives to setup a raid 5 array?

I currently have 1 hitachi 1TB drive 7200rpm 16mb cache and was looking at getting 2 new drives probably the new samsung f3's 1TB

Will I be able to setup these 3 drives in raid though?

Cheers

rpstewart · 16 Sep 2009 at 15:56

Yeah, you'll be able to use them fine. The main problem with mismatched drives in RAID5 comes if you need to replace one of them and the new one is slightly smaller (it can happen even for drives labelled the same size). In that case you can end up being unable to rebuild the array.

mattyj1085 · 16 Sep 2009 at 16:05

Cheers I thought as much, drives ordered so they should be here tomo,

Another thing will I get a performance hit using the onboard raid controller? am I best sourcing a standalone controller card?

Slime101 · 16 Sep 2009 at 16:14

Standalone controllers are best, faster, more reliable and easier to rebuild arrays from however they cost a lot for a proper hardware solution and unless its a business server there is little point.

I have a raid5 setup that even at full pelt only uses 5% CPU, so its hardly the big overhead you see talked about a lot - it might have been years ago but these days its negligable.

AbsenceJam · 16 Sep 2009 at 16:25

The F3's are really fast so you'd be limiting them a lot with the Hitachi disk in there.

lay-z-boy · 16 Sep 2009 at 17:05

mattyj1085 said:
Cheers I thought as much, drives ordered so they should be here tomo,

Another thing will I get a performance hit using the onboard raid controller? am I best sourcing a standalone controller card?

I tried raid 5 with windows software and intel ich, both were quite simply rubbish.

Got 3 new perc 5/i's from ebay for £50 and a battery for a tenner.
(lets you use the onboard 256/512mb cache) 8x 500gb drives in raid 5 is damm quick.

I'll add, I started with 3 drives and slowly added a few drives from my old server and a few that had come back from rma.

mattyj1085 · 17 Sep 2009 at 08:23

If I start off with a 3 drive array can I expand it at a later date without having to rebuild it?

mattyj1085 · 17 Sep 2009 at 09:33

After having a quick search around on a certain auction site I've found a AAR-2610SA/64 SATA ATA RAID that seems to meet my needs does anyone have any advice on whether this card is any good or not if not can some one recommend me an alternative.

rpstewart · 17 Sep 2009 at 09:36

If the controller supports online capacity expansion then yes you can expand it however:

1) It'll take a while
2) Expanding the array won't expand the partitions on it
3) A 3 x 1Tb array will be slightly under the 2Tb threshold for an MBR drive so unless you start off with it initialised as a GPT volume then you won't be able to access any extra space you add to it.