RAID5 for Linux

[Bob Gorman]

At 05:32 PM 4/27/2004, Mark J. Dulcey wrote:
>Bob Keyes wrote:
>>At my new job, we have a NAS "Snap Appliance", which is pretty horrible
>>and I want to get rid of it. So I am going to push for a Linux solution.
>>I'd want RAID level 5, and Serial ATA drives, and of course linux
>>niceness. I was looking at the Adaptec 2810SA, but it's got 8 ports..I
>>though you needed 9 for RAID5 (one for each bit plus one parity) or am I
>>misunderstanding this? I'd also want hot-swappable. Anyone have any
>>suggestions?
>
>RAID 5 can be done with various numbers of drives. The Linux software RAID support, for instance, works with any number >= 3. You can read about that at http://www.tldp.org/HOWTO/Software-RAID-HOWTO.html
>
>Of course, you're looking at a hardware product rather than software RAID. However, the requirements should be similar. The Adaptec data sheet says that card supports "up to 8 SATA drives"; that phrase implies that it will also work with a smaller number. The data sheet, alas, is vague about exactly how many you DO need.
>
>As for hot-swapping, the card handles it, but you'll also want some sort of way of mounting the drives to facilitate swapping. (Opening up a typical tower box, unscrewing drives, etc. probably isn't what you have in mind.) I don't have any suggestions there, but I'm sure somebody on the list will.

Adaptec sells a 4-drive internal enclosure for this.  You can also look into third party disk enclosures, internal or external, to keep the price down.

While I am a fan of Adaptec products, a lot of people like Promise too.

-- 

I build Linux business solutions in the Boston area.
mailto:bob(at)rsi.com, http://www.rsi.com/, 617.965.1700