Adaptec termination problem...

[Robert G. Brown]

> The IBM storage site is at: www.storage.ibm.com

I'm giving this a try right now.  Looks like "pins 9 and 11 of the
auxiliary connector on the 68 pin model" is what I needed -- and the
one thing totally undocumented on the faceplate of the drive.
Needless to say, my system vendor has been clueless.

My crashes (which have persisted now through SMP and UP kernels,
through restriction of the recognized memory beyond sane bounds,
through various permutations of configuration and kernel parameters,
and which are absolute, instantaneous and produce neither oops's,
aiee's, deadlock messages, nor anything else useful to debug) have all
the earmarks of SCSI termination problems -- from my previous
experiences with same.  System sinks without a trace in midstream
under moderate to heavy CPU load associated with lots of disk activity
and otherwise runs totally uneventfully.

If this fixes this particular problem, it is probably worth
documenting in a FAQ or two -- the symptoms of "totally inexplicable
crash" in a SCSI-base system should be linked with "check termination
on onboard SCSI drives for vendor screw-up".  It is probably a
sensible thing to add to your purchase/configuration checklist as
well:  "Make sure that vendor either sets termination jumpers
correctly OR provides cable or device terminators at the ends of
internal/external SCSI cables".

  rgb

Robert G. Brown	                       http://www.phy.duke.edu/~rgb/
Duke University Dept. of Physics, Box 90305
Durham, N.C. 27708-0305
Phone: 1-919-660-2567  Fax: 919-660-2525     email:rgb at phy.duke.edu




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