Software RAID

[skattrd]

I've never tried RAID of any type but shall soon have 3x 36GB drives in my system, so thought this is a good time to try.
What I am contemplating is using windows to create a software RAID setup (my scsi controller 29160 can't do hardware raid afaik) - I have still to decide what type of setup, but as I will require dual boot (2kpro/XP pro) I don't think raid 5 is an option really or is it?
So I will probably be looking at mirroring 1 drive and having the other completely seperate - is windows any good for doing this, or should I consider looking around for a cheapish scsi raid card?

[Steve]

The majority of RAID implementations on non-server motherboards are infact software. Software in the sense that the CPU does all of the work. Sillicon image SATA RAID... that's software, infact some Linux guys wrote a clone of it.

Anyway. Windows RAID requires you creating dynamic disks. I have found, through experience, that they have some limitations and can be quite the pain to work with.

Try it if you really want, but read the windows help files first.

[nichomach]

First prob you'd have is that software stripe sets in Windows are not bootable, so RAID5's out of the window. You'd really be left with two options; mirroring the boot drives and having one standalone, or booting off one drive and either striping or mirroring the other two, but you'd only be able to create a RAID0 stripe set with your two remaining disks. TBH, if you're running Ultra160 drives, I can't see why you'd need to use RAID at all, and I wouldn't bother with it, unless you wanted to combine two of your drives into s stripe set for a single 72GB drive, which I can see maybe being worth it. I wouldn't, your disk subsystem should be pretty damned fast as is, but that's just me.

[skattrd]

Ok, I give up according to M$ can't do raid 1 or 5 with XP/2k pro - needs to be server ..... and my AiW TV doesn't work with 2k server

edit: I was mainly considerring RAID for fault tolerance as I have had 3 drives go tits up on me this year already, thats why I was looking at mirroring or raid 5 - the drives are fast enough as it is really

[Steve]

Heh, I knew you'd be put off, and the points Nicomach mentions are the "limitations" I mentioned.

When I tried it, I did RAID0 in XP. I had a 5GB simple partition on one disk which was the bootable OS partition, a 5GB simple on the other (backup partition,) then the remaining space was RAID0.

I think it lasted about a week before I ditched it.

[skattrd]

Ok, contemplating hardware RAID then - Adaptec 2100S or INTEL SRCU31A (both are u160) any comments or experience of either of these cards ?

[Steve]

Looks like an awful lot of money.

You sure its worth it?

[skattrd]

No it isn't worth buying a new raid card for £300 or so ......
I've got the drives and can pick up one of those cards for about £60-70 secondhand, then sell my 29160, so it isn't alot of money really

[Steve]

Well in that case, have you thought about RAID 5? You'd get some fault tolerance in there too.

I'm getting RAID 5 next week, so keep an eye out for feedback!

[skattrd]

Raid 5 was what I was considerring (see earlier post) as the drives are 3 x 36gig Seagate cheetah's.
I'll have to read up a bit on before I decide to go for it as I'm unsure of how much tolerance you actually get.

[Steve]

Oh yes, indeed you were, sorry!

Well, RAID only gives you protection against hardware failure, but if one of the three drives pops its clogs you can carry on until it is replaced... that's the idea anyway.

[nichomach]

And it works - although be VERY sure you've configured the utilities so that you get notified when a hard disk goes wonky, otherwise, a) you might not notice, and b) if a second goes, you'll have definitively widdled upon your french fried potatoes, to paraphrase Dog Soldiers...

I speak from (painful) experience...

[Steve]

Would the BIOS on bootup not give you a clue nichomach?

[nichomach]

a) Not always, depends on the RAID controller
b) You always watch the POST like a hawk when you power on your machine?
c) You want to know when the disk fails, surely, which can be any time the machine is running.

[Steve]

Too true, though I'd hope a decent RAID controller might beep at you if things went a bit wrong...

The more ways to warn the user, the better, especially in an environment where RAID 5 is likely to be used.

[Butuz]

Most SCSI raid controllers come with software that will beep or email or txt you if a drive fails i think.

Butuz