software RAID vs. hardware RAID controller

[all420]

I want to set up RAID on my new rig. I was originally planning on going with a hardware RAID controller, but then I started thinking about software RAID controllers. I will be running Linux (and maybe a few other Unix OS's like Solaris), and Win2k Pro. To the best of my knowledge, both these OS's support sofware RAID. Therefore, what are the pros/cons of software RAID over hardware RAID? I know that software RAID will chew up more of the system resources (I am going to have dual Xeon 1.7 gHz, over half a gig of RDRAM, etc. so I don't think that will matter). Can software RAID only do certain levels, i.e. 0 or 1? Are the parity algorithm's not as well designed? I would like to set up my HDD's in level 5. Is it best just to buy a cheap hardware controller of Ebay?

[donny_paycheck]

Most OSs support level 5. WinNT does it well. I'd get a hardware controller for the simplification of it and the added security, but since you'll be strapped with mad computing power then software won't slow you down. Whatever you do, do level 5 for sure! It's fast and very secure. If I had critical data here then I'd be doing it too. Also, adaptec makes an ATA RAID-5 controller (I think it's the 2400S or something) that doesn't need U160 or fibrechannel drives, so if you're tight on cash that'd save you some $$....I think the controller's like $300 but drives would be cheap, esp. for 3-4 of them.

[PolyPill]

If this is a mission critical server don't go with software, hardware is more reliable and much faster. Also software can be a pain to get setup, I've only done it with Redhat, which makes it easy, but I know other distributions don't even give you the option.

Also software gives you all levels, 0-5, along with 0/1 and 0/5.

[chaim79]

If you want to do this for your own stuff and don't need high specs I would go for the cheepest hardware RAID card I know of, a promise ultra 66 (and ultra 100) ide controller card. There is a mod out there to make it into the promise ultra 66 RAID card, with just a very small mod. Aparently they built both from the same card and made only one small change (and different bios) to really tell the difference.

The card can be found for cheep, last I saw I could have picked it up for about $20. I would try it but I don't have the $ for even 2 hard drives to try it out.