[net.bugs.4bsd] Cold load on a VAX785

steve@dartvax.UUCP (Steve Campbell) (06/28/85)

One of our 4.2BSD systems began life as a VAX750, cold loaded from the
Berkeley distribution tapes.  Then it became a 780, but the disks were
the same, so no cold load was needed.  Then it became a 785, and again
the same disks were used (though a different boot floppy), so again no
cold load.

Last week after accidently corrupting those disks' root partitions, I
tried to cold load the "miniroot" from those dusty 4.2 floppies and
tapes.  The stand-alone copy program complained of unexpected attention
interrupts from the TU78, but copied the miniroot into the swap area
anyway, and it booted fine.  But when I tried using the miniroot to
restore an "a" partition either from our dump tapes or from the 4.2
distribution tape (!), the restore would die after reading about half
the files.  The system would hang and drop the port access light on the
disk (ra81).  It was a dark hour.

It turns out we also have Ultrix [TM Digital Equip. Corp.].  I tried the
same procedure with their floppy and tape, and - lo! - it worked fine.
No mt attention complaint and a successful restore.  Thanks, guys.

How come?  Do old 4.2 distribution materials not work with 785's?  If
so, 785 folks could have a problem.  Or could other devices now on the
785 - a DEUNA and an INCard - break the Berkeley miniroot?  Anyone know?

					Steve Campbell
					dartvax!steve
					steve@Dartmouth.CSNET