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sunsite.doc.ic.ac.uk:/public/unix/NetBSD/arch/sparc/snapshot/19991024

This machine has 2 disks, using Solaris on  sd0  I formatted sd1 with
3 partitions:

a: 40   cyl  intended for  /
b: 130  cyl  for swap
c: whole disk
g: 2500 cyl  for  /usr

Copied miniroot (  ./installation/miniroot/miniroot-14L.fs.gz  )
to a local server, un-GNU-zip, copied it by  dd onto  /dev/rsd1b

Reboot from  /dev/rsd1b  proceeded with install, no visible errors.
Copied all the sets from  ./binary/sets  to a local server, miniroot
installed them by  ftp ,  again no visible errors after I learnt 
from my mistakes.  

Detached  sd0  try to reboot from  sd1  using

boot disk1 netbsd -s

floods of messages, ending with  

root on sd0a dumps on sd0b 

and a shell prompt.  My problem is that the root drive  /  is mounted
read-only & I cannot reconfigure anything.  

mount              says

root_device on / type ffs (local, read-only)

mount -u           says

mount_ffs: /dev/sd1a: on / :  specified device does not match mounted
device

mount -o remount   says

mount_ffs: -o remount: option not supported

I tried  boot disk1 netbsd -as

but dont know how to answer its questions.  At any rate when it asks
for a root device it wont accept  sd1a ,  it insists on le0 or fd0 or
sd0[a-h]

I can find nothing about this in the Install documents.