On Mon, 27 Aug 2001, Alexander Klein wrote:

> While I was trying to set up my system for RAID 1, I had to reinitialize
> one of my HDs.
>
> Unfortunately, however, on all the disks that I'd worked on with disklabel,
> the partition maps were unreadable for the Mac (which wasn't much of a
> problem), and the one I tried to format only gave me an error about the
> magnetic media format being corrupted.
>
> Further investiagtion showed, that it's really an error detected by the
> drive, not only HD SC-setup. The drive knows its type, but doesn't know
> about bad sectors and a lot of other things.
>
> Is it really possible to physically trash a SCSI-Drive with disklabel???

Evidently. I once got a drive to where the Mac wouldn't boot with it
attached. The disklabel probably overwrote some area in block 0
reserved by the Mac OS driver.

Using a real BSD disklabel is not compatible with using the drive for
any purpose under Mac OS (if it works at all). The "normal" way is for
NetBSD to fake the label from the Mac OS partition map.

> And has anyone any idea what could be done to revive the disk?

Boot into NetBSD and use "dd" to zero out the first 32k or so. The Mac
OS tool should then recognize the disk as a clean, new disk, allowing
you to format and partition it. Alternatively, you could try zeroing
out the partition map, applying a NetBSD disklabel, and only using the
drive under NetBSD. If the Mac firmware sees no partition map
signature, the Finder will just ignore the drive (but partitioners and
disk tools will still be able to see it).

Frederick