Submit Hint Search The Forums LinksStatsPollsHeadlinesRSS
14,000 hints and counting!

10.4: Install Tiger on improperly set up RAID drive Install
Tiger only hintThis is more like an un-hint. Previously, I had set up a mirrored RAID array per this hint. It all seemed to be working so well, until I tried installing Tiger. The Tiger installer had major issues when attempting to verify the installation disk (my RAID drive). Although well-warned, I did not have a backup (who needs one with a RAID 0 array?).

The fix is pretty straightforward, but somewhat tedious. After the Tiger installer lets you know that everything is hosed, power down the computer. One at a time, disconnect one of the drives and attempt to boot off the still-connected drive. In my case, one drive would boot and was shown in Disk Utility as a "degraded" RAID drive. The other drive would not boot at all.

Pay very close attention to which one is the "good" drive. Confusingly, Disk Utility shows the unbootable drive as the drive in the RAID set and the bootable drive as on a separate volume. The only information that seemed to make sense was the disk location info which tells you whether the drive is in the upper or lower bay.

Once you are satisfied that you know which disk is which, erase the unbootable disk. Then use Carbon Copy Cloner to clone your "degraded RAID disk" to your newly initialized disk. When that is done, boot up on the newly cloned disk, delete the RAID set, then clone back. In my case, just to be sure, I first verified I could boot off the newly created disk, then I unplugged my newly initialized-and-cloned disk, and booted off the Tiger install disk. From there, I deleted the RAID set and re-initialized the drive.

There's some morals here, I'm sure. In my case, I plan to pay better attention to the numerous warnings about attempting unsupported hacks.
  • Currently 1.83 / 5
  You rated: 1 / 5 (6 votes cast)

10.4: Install Tiger on improperly set up RAID drive | 7 comments | Create New Account
Click here to return to the '10.4: Install Tiger on improperly set up RAID drive' hint
The following comments are owned by whoever posted them. This site is not responsible for what they say.
10.4: Install Tiger on improperly set up RAID drive
Authored by: rufo on May 04, '05 12:40:04PM

Personally, I would've just dropped to the command line, told the good drive to be a single-volume RAID, then wiped the second drive and rebuild the mirror onto that.

Also, just because you have a mirrored RAID doesn't mean backups aren't important. If some rogue process goes through and wipes your hard drive, or you suffer from directory corruption (it's happened to me even with journaling turned on), or you accidently run some command that goes through and wipes out your home folder... your mirrored drive isn't going to be of much help I'm afraid.

[ Reply to This | # ]
10.4: Install Tiger on improperly set up RAID drive
Authored by: dcoyle on May 04, '05 08:47:36PM

The particular issue was that Panther had absolutely no problem with the RAID setup created by following the earlier hint. There was nothing to repair as far as Panther was concerned. After creating a RAID pair, I checked several times to see if there was any problem and never saw a reason to worry.

The Tiger software is apparently much less forgiving and expects a "by the numbers" RAID set. By the way, I don't in any way mean to impugn the originator of the post I followed. There were sufficient warnings and it seemed to work just dandy under Panther.

I know you're just trying to make me feel worse by pointing out that I wasn't buying myself much by getting into this jam in the first place. Please see my reply to diamondsw. But thank you sincerely for your input.

[ Reply to This | # ]
10.4: Install Tiger on improperly set up RAID drive
Authored by: rufo on May 05, '05 09:23:11AM

Eh, my intention wasn't to make you feel worse, although I had a rough morning yesterday and was kind of in a cranky mood, so I may have come off that way. My apologies. :-)

You still could've set the other drive as a single volume RAID and rebuilt the mirror though... in the Tiger installer you can drop to the command line and probably run diutil from there (although I haven't actually seen if it has diutil), and then right from there you can head into Disk Utility, wipe the extra drive and rebuild the mirror.

I still think not having any sort of traditional backup is a Bad Idea though. You can be extremely careful and choosy about what sort of software you run and still lose data due to some freak accident - just look at the one iTunes installer package that erased data on any secondary hard drives that had a space in the name because of two missing quote characters. And it doesn't take a freak accident to cause directory damage, just a misplaced power surge or kernel panic. (I don't trust journaling fully since as I said, one of my biggest directory corruptions came while it was turned on... I do believe it prevents most damage but I'm uncertain of it's real capabilities.)

Still, if you want to run without a Real Backup™, fine by me, and if you happen to have all of your important data on a server somewhere or you just don't care if your data is lost then seriously, that's great - just don't complain if something *does* happen. :-)

[ Reply to This | # ]
10.4: Install Tiger on improperly set up RAID drive
Authored by: sap.1 on May 04, '05 01:04:06PM
How to rebuild a software RAID mirror

From Apple's site; seemed relevant.

[ Reply to This | # ]

10.4: Install Tiger on improperly set up RAID drive
Authored by: diamondsw on May 04, '05 03:15:50PM

I hope this hint is wrong - "who needs backups with a RAID-0 array"? You do - RAID-0 has no redundancy, and is much more likely to fail than a single drive (if you have four drives, for example, you have four times as many points of complete failure). Even if you meant RAID-1 (mirroring) you still need backups as a RAID-1 will faithfully copy directory corruption from drive to drive - RAID-1 only protects against hardware failure.

[ Reply to This | # ]
10.4: Install Tiger on improperly set up RAID drive
Authored by: dcoyle on May 04, '05 08:33:16PM

I meant mirroring. I understand RAID concepts pretty well, but forever get confused with whether RAID 0 or 1 refers to mirroring (for safety) or striping (for speed). At work, everything I control is RAID 5. Your point is well taken, however. My biggest fear is a disk failure, which I can't control. I'm pretty careful with what I install or do that could cause a corruption issue, although you could be forgiven for thinking the opposite after reading about this latest attempt at getting by on the cheap.

[ Reply to This | # ]
Worked fine for me
Authored by: JohnDCCIU on Jun 24, '05 05:23:19PM

Three Panther machines that I "converted" to RAID 1 using the same article, then later updated with Tiger, are all working fine.

Two of the three did have a disk problem of some sort, but that was easily fixed with DiskWarrior (before the Tiger upgrade), and then the upgrade went fine. All three have been humming along on with Tiger on RAID 1 since they were upgraded.

[ Reply to This | # ]