Do you know that the members of sun-managers are faster than e-mail ??
(I got many responses before I got the copy of my question ...    :-)
And as you can see with that smileys above, you solved my problem.
Thanks goes to:
Charles Gagnon    Charles@Grafnetix.COM
Jens Fischer      fischjns@kat.ina.de
Volker Sander     V.Sander@kfa-juelich.de
Stephen Harris    sweh@mpn.com
Caspar Dik        caspar@holland.Sun.COM
Charles Homan     choman@applic.com
K. Ravi           RAVKRISH.IN.ORACLE.COM.ofcmail@in.oracle.com
Luca Pizzinato    pizzinato@eumetsat.de
Tim Buller        buller@math.ukans.edu
Brett Lymn        blymn@awadi.com.au
Gary White        Gary.White@ramstein.af.mil
Marina Daniels    Marina.Daniels@ccd.tas.gov.au
...
Original question:
> I've a Sparcstation 5 wich has been crashed (problem with cpu...)
> So I tried to move the boot-disk to a new Sparcstation 20 and tried
> to boot, no success!  
> 
> The root-filesystem is recognized (I think so), but the Sparcstation 20
> cannot mount the /usr-filesystem! (The disk on another Sparc5 is working
> (but I cannot access the other Sparc5 for a longer time ...)
> 
> Can anyone help on moving my boot-disk from Sparc5 to a Sparc20 ??
Solution(s):
----
  1. swapped in the 20, using the OS disk from the SPARC 5.
  2. boot single user to the solaris cd. (boot cdrom -sw)
  3. mount /dev/dsk/c0t3d0s0 /a   (assuming the boot disk is target 3)
  4. cd /tmp/dev; tar cvfp - . | (cd /a/dev; tar xvfp -)
  5. cd /tmp/devices; tar cvfp - . | (cd /a/devices; tar xvfp -)
  6. cd /tmp/root/etc
  7. cp path_to_inst /a/etc/path_to_inst
  8. halt
  9. boot -r
----
----
What you need to do is change the board, boot from cdrom and mount the disk
(say on /a).  Remove the contents of the /a/dev and /a/devices
directories.  Copy /etc/path_to_inst to /a/etc/path_to_inst.  Then do:
drvconfig -p /a/etc/path_to_inst -r /a
devlinks -r /a
disks -r /a
----
----
Check out the summaries at
  "http://www.dataman.nl/cgi-bin/sunmanagers"
This has been answered in good detail a few times.
----
----
echo "#path_to_inst_bootstrap_1" > /etc/path_to_inst
Followed by "boot -r"
----
----
Boot from CD; 
Mount rootdisk on /a; 
 
mv /a/etc/path_to_inst /a/etc/path_to_inst.old 
cp /etc/path_to_inst /a/etc 
cd /devices 
rm -rf * 
cd /dev 
rm -rf * 
drvconfig -p /a/etc/path_to_inst -r /a 
disks -r /a 
reboot -- -r 
----
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    o      |   __   |          |  Christian Masopust
      \_ O |  |__|  |          |  System Administrator
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