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Mac's Tiresome Software RAID

I'm trying to upgrade to Leopard (or is it Blotched Tabby? I can never keep their kitty cats straight) a.k.a. OS-X 10.5.

When I first got my Mac Pro, I looked at the lovely array of hard drive bays and said, "RAID!"

So I decided to RAID my system drives. Now I'm trying to un-RAID them and use Time Machine, and OS-X is being a pain about it. Actually, the RAID system has been a pain all along (I wrote a bit about this before).

There are lots of ways to back up working documents, but the biggest recovery pain these days is to restore 3rd party applications (too much stuff from Adobe, Open Office, Redmond's stuff, etc.). Licensed stuff is the worst, since you have to search out the license codes and type them in yet again.

To forestall this hassle, I RAIDed my system volume. Not having the extra stack of hundreds to throw at the hardware RAID board, I used the built-in software RAID. All these comments have to do with the software version.

It's a pain to RAID the system volume. Fortunately I researched it while I was acquiring the Mac Pro, so I knew what to do when the box arrived. First thing you do is THROW AWAY THE PRE-INSTALLED OS. That's right, you can't RAID a working system volume. You have to book from the distribution DVD, use Disk Util to RAID two blank drives, and then re-install the system.

Say 'good bye' to any free apps they happened to install on the original system. I decided it was worth it for the improved reliablity.

Anyway, I've been running RAIDed for about 8 months. Now I want to upgrade to OS X 10.5. I thought about upgrading the RAIDed system, and decided against it. My son told me that he'd had trouble upgrading an older 10.4 system because of file system incompatabilities, and I'd hate to run into such problems with my RAID configuration.

Disk Util provides a button to 'delete' a RAID set, but they warn of possible data loss (??). To forestall that risk, I pulled one of the RAID drives out of the Pro, powered up, and then tried to delete the RAID set from Disk Util.

No go.

I started up Disk Util and I selected the RAID set. Util showed the set as 'degraded' since it was missing a drive. I went for the 'Delete RAID Set' operation (a button marked 'Delete'). The button was disabled.

Ugh. So I have to risk the whole damn RAID set just to be able to delete a piece of it. They say it's risky to delete a RAID set, so why fergoshsakes do they force us to risk both halves? There are already lots of different ways of messing up a RAID set - why make this part hard, too?

Since I had booted the system with part of the RAID set missing, I had to erase the spare drive, reinstall it, and rebuild the mirrors. This is because Disk Util mindlessly assumes that if a drive was ever a part of a RAID set, then it must be an up to date part of the RAID set.

Now I'm rebuilding the RAID set and waiting impatiently while several gig of important personal files likewise get copied onto an external drive for safekeeping.

Once this tiresome process is over, I should be able to install 10.5 and, hopefully, I won't lose my system volume when un-RAIDing.

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