watchdog reset

[Daniel Ehrlich]

In article <718 at brazos.Rice.edu> titan.tsd.arlut.utexas.edu!kam at cs.utexas.edu (Katherine Minister Hosch) writes:

Howdy all.  This has happened twice now, and I'm starting to get a little
worried.  We have a standalone 4/260 that crashed the other day, leaving
only the message (on the console):

	   > watchdog reset

We have been seeing these on a regular basis on our `new' 4/280S.  A
question, is your 4/260 equipped with the FPU2 floating point daughter
board?  If the CPU occupies slots 1 and 2 it probably does.  In any event
our problem seems to be related to having the two 7053 disk controllers
trying to access the VME bus at the exact same time.

I rebooted, and ran fsck, but it didn't seem to have any big problems.
Today it crashed again, with the same console message.  The messages file
didn't contain anything the first time, but the second time there was a
message from two days ago about a memory failure:

Jul 29 13:48:41 mars vmunix: mem3: soft ecc addr 4ce550 syn
5b<S16,S4,S2,S0,SX> 41 U1841

Somehow I suspect that the message is unrelated to the reset though.

My question is this:  what *causes* a 'watchdog reset', other than pushing
the 'reset' button on the back of the machine?  In neither case was the
button pushed.  

What I have been told by the folks at Sun is that the 'Watchdog reset'
occurs when there is a double bit parity error on the VME bus.

This sounds like a bad problem to me; does anyone have any ideas about it?

Sun's standard response is to replace the CPU board.  Although this may
not be the real cause of the problem.

   Katherine Minister Hosch:		kam at titan.tsd.arlut.utexas.edu
   Applied Research Laboratories		(512)-835-3148
   University of Texas at Austin
   P.O. Box 8029, Austin, TX  78713-8029

--
Dan Ehrlich <ehrlich at shire.cs.psu.edu> | Disclaimer: The opinions expressed are
The Pennsylvania State University      | my own, and should not be attributed
Department of Computer Science         | to anyone else, living or dead.
University Park, PA   16802            |