I'm not sure if this is the reason, but I would say either:
1. set the new drive to target 0
2. edit the /etc/fstab file to reflect the change to target 6 (see the
device section... I think that is what would need to change, man fstab
> I have an oldish server running 2.1.5. It has one SCSI disk, on target
> 0 and a CD on target 6.
> The disk is getting on and starting to show signs of impending
> failure. So I have obtained a new disk, and temporarily removed the CD
> and fitted the disk in its place. I set it up as SCSI 6 for no other
> reason than that was used by the CD.
> I have used fdisk and disklabel to create partitions, and I have used
> a dump/restore pipe to copy over all the partitions from the old disk.
> At this point the old disk is called sd0 and the new one sd1.
> If I then just remove the old disk and reboot, it starts to boot just
> fine from the new disk, which is now seen as sd0. However at some
> point during the boot, presumably when it starts mounting filesystems,
> it throws up a "panic: can't mount root", and restarts.
> All the partitions on the new disk are fine, I can mount them without
> There is an entry in the FAQ about this error, but it is written for
> the situation where IDE drives are being used, not SCSI, so I don't
> know how relevant it is. It states the problem is due to the boot
> blocks having a record of the root partition which is not one the
> kernel can deal with.
> Question: how can I determine/change the boot block's view of what the
> root filesystem is on a 2.1.5 system?
> Jim Hatfield