Thanks again Pmax-ers

I got lots of suggestions about SCSI termination, cabling etc.  Let me
elaborate some answers on each aspect as I know it.


>From Tohru Nishimura

>You have RZ25 disk with SCSI# set to 5.  NetBSD/pmax kernel does not
>make the disk usable because it uses old SCSI machinary and disknames
>is "wired" with SCSI ID number.  ID 5 and 6 are reserved for SCSI tape
>drives. 

Yes, but I'm running Ultrix on RZ25 (rz5) but running (or trying) to run
NetBSD on RZ23 (rz3).  I don't see why a disk drive that can't be seen
(at this point) would cause any problems.  Still, I can remove / change
it.

And another from Tohru

I've run across yet-another-possibility (during taking dinner).  Jason,
your machine has an external housing holds RRD42 and RZ25, right?  My
(might-sound-dumb) question is; if so is your SCSI cabling/termination
configured properly?

Yes, the cabling is configured "per the book", and I have a terminator
on either the system unit (without external SZ12 expansion cabinet) or
on the SZ12 (when I connected it up).  Funny thing is that an RZ25 in
the SZ12 cabinet actually works OK.  In my book, that goes a long way
toward ruling out SCSI problems.

BTW, the RZ23 in the system box is connected as the FIRST device on the
SCSI chain, then to the RZ23 and then to the RRD42.

There isn't some new-fangled version of RZ23 drive firmware that I
should be running (anyone care to advise what RZ23 and RZ25 firmware
they have ?)

And then another from Tohru (gee thanks for all your help !!!)


More interesting.  It seems a corrupted kernel image, but given
inconsistent results, I'm wandering something wrong is in RZ23 disk
hardware itself. 

I will try putting another RZ23 in the place of this one, and give it
another go, just to be sure.

I recommend you to start from 1.3_ALPHA/pmax distribution set, not
anything in arch/pmax directory.  It's unlikely people can suggest you
solution with getting-obsoluted snapshots, because people's focuses is
now completing 1.3 distribution kit as soon as possible.  Your feedback
will help many.

I have downloaded it overnight, and will give some feedback in the
coming days as my free time allows.

And then from the master himself, Jonathan.

This *has* caused several people real problems in the past.

If memory serves, Maximum Entropy had some nasty problems with initial
installs due to bad or marginal SCSI cables and poor termination --
even though Ultrix coped with it just fine.  Replacing the SCSI cables
solved that problem completely and permanently

This can be a particular problem with the 3MIN chassis (5000/125) with
the long cables that go under the CD-rom housing; they need
extra-special attention when installing or removing drives, and with
proper termination.

OK, the cabling looks "textbook".  I don't really want to go around
swapping cables willy-nilly if I can help it.  However, the RZ23 is on
the first connector along the chain, so I would have thought that would
be more than adequate.  I *may* have a ribbon-style SCSI cable (rather
than the standard DEC "bundle") that I can try, to see if this makes
things better.  Or, I could try disconnecting the "downstream" devices,
leaving just the terminator.

Any suggestions on "extra-special attention" that I should be paying to
these, or the best way to lay them out ?

PS: Can anyone confirm for me that I'm on the port-pmax mailing list ?
I sent a request via the Web, and replied to majordomo's confirmation
message.  However I am only getting one copy of each of your replies
(though they're send to me AND the list).  This has to be the most
contrary (and perhaps bizarre) majordomo I've ever dealt with.  Still, I
guess it's just trying to keep people from subscribing their friends
.....

Regards

Jason Armistead