At 11:59 AM -0400 6/25/07, Christopher Waltham wrote:
...has anyone seen this kind of behavior before?
I have a G5 Xserve running 10.4.8 Server, with a pair of 80GB
drives in a RAID1 array. One of the disks became degraded this
morning, but diskutil didn't fix it automatically. This seems to
be because the array was created in 10.3.9 Server (i.e. Panther),
and thus was made with AppleRAID version 1.
Yes.
So, I booted off a 10.4 install DVD and ran "diskutil convertRAID"
to convert the array to AppleRAID 2 so that I could repair it. The
logs from diskutil say that everything went flawlessly and it only
took a couple of minutes to complete. However, upon rebooting the
Xserve after that, the RAID array exists but the volume it
contains has seemingly disappeared.
You performed this operation against a "bad" array? That would not
sound like a very wise idea.
I should have added that I tried to repair the array manually, i.e.
with "diskutil repairMirror", but had no success either. I recalled
that, several months ago, I had run into the same problem on a G5
PowerMac with the same circumstances -- i.e., a Tiger OS with a
Panther-created RAID 1 array.
When trying to run repairMirror on a Panther array in Tiger, both on
the PowerMac and the Xserve, I got the same error message. I don't
exactly remember what it was, but I'm sure I can re-create it. My
hunch was that you simply can't repair a Panther-created mirror in
Tiger -- is that incorrect? Both times I have tried to do it, it has
failed.
FWIW, when I encountered the problem with the PowerMac's array, doing
a "diskutil convertRAID" before fixing the array worked flawlessly --
which is why I didn't hesitate to do it this time.
What do you mean by the RAID array exists but the volume doesn't.
Either it has an entry in the device table or it doesn't.
Well, the array shows up in Disk Utility (icons for both physical
drives, and then the icon for the logical drive) but the volume's
entry in /Volumes is different to what I'd expect. Perhaps I'm
getting my nomenclature wrong?
If you are referring to the volume mounting, rather than existing,
then refer your commentary above where you tell us it was "bad".
I'm back to booting off the install DVD, because OS X can no
longer find it's boot partition.
Well probably can't mount it, from your comments above, so it
wouldn't be able to boot from a disk that's bad and can't be mounted.
Well, yes, but I tried booting from it *before* mounting it, as I had
no reason (i.e., a lack of error messages) to suggest that there were
any problems with the array.
Disk Utility, when launched from the DVD, says that the array is
Online but both disks that used to house the array are Offline.
Strangely, it reports the name of the volume as being "Macintosh
HD" instead of "pinkham", which was the name of the volume before
I ran diskutil on it.
Sounds like the volume has been modified.
When I run the "Verify Disk" command in Disk Utility on the RAID
volume, I get this error:
"Invalid volume header
Invalid b-tree node size"
Again, you took a bad volume and made it worse.
So this brings us back to my original question: can you run
"repairMirror" in Tiger on a Panther-created array? Both times I have
tried, diskutil has complained before starting the conversion process.
Short of buying a copy of DiskWarrior, does anyone have a fix for
this?
It was very simple from the beginning. Reformat your RAID to a new
Apple RAID v2 partition and restore the RAID from your last known
good backup.
...if that is a "no" to my previous question, then frankly I think
this ought to be better explained by Apple. Because what it means is
"If you have a RAID array in Panther and you upgrade to Tiger,
convert your RAID immediately -- otherwise it's useless, because when
it fails it can't be repaired". If that's the case, I think it's
quite silly; especially how the Tiger install DVD (when updating from
Panther) says nothing about needing to convert your RAID.
DIskWarrior, FWIW, is highly invasive and generally not recommended
[MNSHO] as it will "repair" the volume creating "lost" files that
are probably corrupted. If this is your boot disk this can result
in unbootable volumes since files can be screwy. If you do use it
realize that the volume that's been repaired is highly suspect.
Yes, I would of course be aware of that caveat. :-)
