[net.unix] Console hangs on Vax 780 4.2BSD

davem@sdcrdcf.UUCP (David Melman) (07/15/86)

This is concerning a Vax 780 running 4.2BSD.

We have an intermittent problem where processes will hang when
attempting to write to the console, a DECWRITER III.  It has been
occuring several times a month.

This, of course, is quite serious.  It even precludes an 'su root'
which must write to the console!

We reboot with great frustration when this occurs, which has
always cleared the problem.

Sometimes this 'hung-console' problem results in a crash with the following
message on the console:

?UNEXPECTED TRAP
	MOUNT CONSOLE FLOPPPY, THEN TYPE ^C  	(operator then types ^c)
	CPU RUNNING, SOMM CLEAR,STEN=NONE,CLOCK=NORM
	RAD=HEX,ADD=PHYS,DAT=LONG,FILL=00,REL=00000000
	(RELOADING WCS)
	?CPU NOT IN CONSOLE WAIT LOOP,FUNCTION ABORTED
	VER: PCS=00 WCS=00-00 FPLA=2F CON=V05-00-L	
?WARNING-WCS & FPLA VER MISMATCH
>>>
	

Any pointers regarding this problem would be most appreciated.

David Melman
System Development Corporation - Santa Monica
(213) 820-4111 X5367

UUCP: {ihnp4,hplabs,sdcsvax}!sdcrdcf!davem

mangler@cit-vax.UUCP (07/16/86)

In article <2879@sdcrdcf.UUCP>, davem@sdcrdcf.UUCP (David Melman) writes:
> Sometimes this 'hung-console' problem results in a crash with the following
> message on the console:
>
> ?UNEXPECTED TRAP

This happened to our 780 a while back.	The console LSI-11 would
take a trap, and need to be rebooted.  Of course rebooting the LSI-11
also reboots the KA780 that it controls.

The problem is that your LSI-11 is BROKEN.  I think in our case DEC
replaced the LSI-11's cpu board, but I'm not sure.  Call your friendly
field circus rep.

Don Speck	speck@vlsi.caltech.edu	seismo!cit-vax!speck