This may seem like a silly question, but are you sure that you have a /dev
tree on your restored disk with valid devices in it?  
When the kernel is asking for input about root and swap, it's not using the
device tree, but when init is asking about a shell, I believe  it is.  I'm
sure you thought of that, so I'm just asking for completeness.
-Brian

On Nov 16, 10:53pm, der Mouse wrote:
} Subject: More 1.6.1 strangeness
} Okay, so despite the problems I posted about earlier, I got 1.6.1 on
} the disk.  Then, because the disk was relatively big (>1024
} "cylinders"), I wanted to do what I've done before with such machines:
} move boot and kernel to a tiny little /kernels filesystem and put root
} on d (e on i386).  So I put the disk on my existing i386 machine,
} snapshotted it to spare space, repartitioned, remade filesystems, and
} restored everything.  Then I moved /netbsd into the new boot partition
} (the tiny one), booted from the install floppies, and ran installboot
} on the boot partition.
} 
} Then I booted ("boot -as").  The kernel loaded fine, prompted for root
} (I typed wd0e), dump (I let it default), and filesystem type (also
} defaulted).  Then it fired off init, which prompted for a shell or
} RETURN for sh.
} 
} But at this prompt the keyboard is dead.  RETURN does nothing.
} Ctl-Alt-Del does nothing.  Ctl-Alt-Esc does nothing.  I've tried it
} three times, being very careful to not touch the keyboard after the
} filesystem-type response the second two times, and it's consistent.  At
} first I thought this might be KBD_DELAY being too low a value (as a few
} of you may recall I reported problems with here quite some time back),
} until I realized that the keyboard (a) worked fine at the
} root/dump/fstype prompts and (b) worked fine from the install floppies
} (which presumably were built with the same KBD_DELAY define as the
} GENERIC kernel I'm using).
} 
} Any thoughts on what might be wrong?  Obviously, a nonworking keyboard
} is a pretty crippling problem.
} 
} Just in case I botched something while rearranging things, I'm about to
} take another snapshot of the disk, then restore the previous snapshot
} (which has one big multi-gig root filesystem) and see if it works
} there.  I don't really expect this to fix anything, but I figure I have
} to give it a try.  (The reason for juggling things at all when my
} machine can demonstrably boot fine from large root filesystems is that
} this disk is intended to be carried to another machine and booted
} there, and I don't know whether that machine is similarly tolerant.)
} 
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