Problems with xy451/CDC Sabre

[Bradford Garton]

Woe is us --

We've been having mucho problems with a Xylogics 451/CDC Sabre 850
combination.  Here's the story (for those interested):

We bought one of the snazzy new "shoebox" disks, a CDC Sabre 850 Mbyte,
along with a new Xylogics 451 to run it.  Got the disk & card, put it in,
all was wonderful for about a month.  Then we got a strange crash from a
bus timeout... no worry (I thought), was probably "one of those things".
One week later we had another.  During reboot fsck died from yet another
bus timeout while working on the new disk.  Brought the machine down and
reseated the cards & cables.  Machine came back up, no problems, not a
single peep from fsck (oh yeah, we had seen no disk errors at all on the
Sabre).  Next day same thing happens, no one was logged on, no user
processes running.  This time during one of the reboots the Sun refuses to
attach the new controller.  So I pull it out, try it in a different slot.
Comes up and runs like a top for about 20 minutes, then the same thing
happens (although now I notice that the machine slows way down before the
bus timeout and that the error occurs when asked to do a disk access to
the new disk -- as you would expect).  Try various combinations of slots
and cables with no success.  Finally the machine won't attach the new card
at all during boot.

"Aha!" I think, "It's obviously the controller card or the VME-Multibus
adaptor!"  I send them back marked: PLEASE FIX THESE SO I NEVER HAVE TO
THINK ABOUT THEM AGAIN.  AVIV (the vendor) runs both for about three days
in their machine, no troubles.  They send them back -- I put them in our
machine, all is fine for about a week and then it all happens again.

I'm about to send the cards back and pay additional $$$ for an
"in-warranty replacement". I lie awake at night, however, and worry that
it might not be the cards at all but the disk or our machine.  Everything
I've seen points to one or the other of the cards -- I can use them in
different slots, the disk never shows any errors (when it comes up it
always checks out fine -- all the data is happily sitting there waiting to
be accessed).  Is it possible that something else could be causing this
problem?  Anybody else seen this behaviour before?

Oh yeah, we're running a Sun 3/280 with SunOS 3.2.  Our main disk is a
Fuji Eagle hung on a Xylogics 450.  System runs fine (and has for a year)
when the new card is gone.

Brad Garton
Music Department -- Columbia University
brad at woof.columbia.edu -or-
...!columbia!woof!brad
(212)280-3825,3434