question for pc geeks: RAID

TimT · 07-27-2008, 03:58 PM

I built a pc a few months ago which can support RAID 0 or RAID 1. I only installed one hard disk when I first set it up inititally.

Can I add a second disk and set up RAID 1 to mirror the original hdd without having to reinstall widows and all my other apps? Or do I have to wipe the slate clean, and set up the array, then reinstall windoze and my apps?

Vipergrün · 07-27-2008, 04:08 PM

Are you talking hardware or software RAID? With either you should be able to do it on the fly without having to reinstall.

The key is that the 2nd disk is at least the same size and speed as the original.

Oh yeah, just make sure you mirror in the right direction

HardDrive · 07-27-2008, 05:24 PM

I am assuming you are talking about hardware raid. In that case, yes you can mirror the drives. You will need to install the drive and use a utility to setup the raid. The software may be available as part of the boot process. If you have a lot of data, it could take awhile.

Back up first.

As state above, the drive should be similar in speed.

I don't know if Vista supports raid.

TimT · 07-27-2008, 05:36 PM

Quote:

Are you talking hardware or software RAID?

Well I'm not sure in that regard. Re-reading the motherboards manual (MSI P4M890)

It describes setting up the array, then installing windoze. Some RAID drivers have to be installed then BIOS set up, then windoze install.

I wonder if I can do all that and retain the integrity of the original hdd? If I set up the array will all the info on the original disc be mirrored onto the new blank disc?

I have a gut feeling that this cant happen, and don't have to do the install all over again.... though I do have some nice homebrews that are just about ready

IN the last year my main pcs hdd took a dump and I hadn't backed up recently, and last week my Toughbook had a motherboard incident... where something let go in a big way.. lots heat and bit of smoke..

Vipergrün · 07-27-2008, 05:45 PM

Looked at the MB specs. Looks like you can RAID the SATA interface? I'd yank your existing drive, install two of the same 7200 RPM SATA drives and reinstall the OS. Assuming you have an IDE drive now, this would bump performance quite a bit.

KaptKaos · 07-27-2008, 08:38 PM

Depends.

Check the RAID controller. Find a forum for that hardware and ask there. It might work or it might reformat your hard drive.

Make sure you are backed up before you try and be prepared to reinstall.

Good luck.

TimT · 07-27-2008, 08:50 PM

Actually the hdd I have now is a ide and its installed with a SATA adapter.. I simply want to add another 160g WD hdd and have them live happily ever after.

Maybe I should just copy the existing drive to the new drive, then set up RAID?

KaptKaos · 07-27-2008, 10:25 PM

When you setup RAID 0 or 1, the hard drive controller will handle the mirroring process. That's assuming its a RAID controller. Here are the challenges:

1) Does the controller support adding a second drive to the existing and creating the array?
2) How does the controller determine which drive is the primary the first time it sees that it has 2 drives attached? If it thinks the blank is primary, it will push the blank image to the other drive, thereby erasing your data. BTDT

So no, just copying your data to the second drive doesn't buy you anything. You need to read up on the procedures specific to your RAID controller and then find a forum where people talk about doing what you are doing and see how it's gone for them.

Good luck!

svandamme · svandamme's Garage

depends on the controller, but Most SATA raid controllers will enable RAID 1 after OS install
if intel, you'll need the intel storage manager installed and then you can enable raid 1 from there

you can't do this with RAID 0 or RAID 5
only Mirroring will work since it only requires a full copy from disk 1 to disk 2
whereas raid 1 or raid 4/5 requires the data to be redistributed, which is tricky....

stomachmonkey · 07-28-2008, 07:34 AM

Which level of RAID depends on your application.

I prefer 5. Most redundancy but you'll need at least 3 discs.

sammyg2 · 07-28-2008, 07:53 AM

I agree

svandamme · svandamme's Garage

raid 5 does NOT offer more redundancy over Raid 1
not one bit

Raid 1 can take 1 disk failure
so can Raid 5

stomachmonkey · 07-28-2008, 10:17 AM

Quote:

Originally Posted by svandamme

raid 5 does NOT offer more redundancy over Raid 1
not one bit

Raid 1 can take 1 disk failure
so can Raid 5

Correct

KaptKaos · 07-28-2008, 01:45 PM

RAID 5 offers better utilization. RAID 0 and 1 offer 50% while RAID 5 can provide up to 80% utilization.

Scott R · Scott R's Garage

Quote:

Originally Posted by KaptKaos

RAID 5 offers better utilization. RAID 0 and 1 offer 50% while RAID 5 can provide up to 80% utilization.

Zero offers 100% utilization, fastest read and write, however no redundancy.

http://publib.boulder.ibm.com/infocenter/eserver/v1r2/index.jsp?topic=/diricinfo/fqy0_cselraid.html

(Have a little writing credit in that doc)

Vipergrün · 07-28-2008, 07:48 PM

RAID 5 will suck when it comes time to rebuild the array in the event of a disk failure. If you want the best do RAID 0+1 on a SAN with a lot of spindles

Remember, though, RAID does not protect against stupidity, deleted files, etc. Garbage in, garbage out.