Bill Studenmund writes:

>Wasn't there some mention of a bug in that one of the scsi chips (on an
>alpha?) was getting inited to the wrong clock frequency? Could there be
>some problem like that floating around?

There *were*, but it's a different model of decstation, and a
different SCSI chip.

I duplicated a 53c94 clock-speed initialization bug from the Alpha
port into the 5000/1xx and 5000/2x models.  That bug is fixed.  I
don't think it has anything to do with the DEC-specific SCSI/DSSI asic
(SII) in the 3100/2100 (aka pmax).

If the 5000s are anything to go by, then using internal disks with the
NetBSD/pmax drivers is probably a mistake. Even if a system worked
under Ultrix. The Ultrix drivers can recover from poor termination
problems that cause the NetBSD/pmax drivers to just give up.

The 4.4bsd/pmax scsi drivers -- especially the sii driver -- have a
long history of unpleasant bugs.  The publically-available
documentation on the proprietary SII chip is good, but not *quite*
detailed enough to write a really good driver.  I think it's safer for
the driver to not try and recover from error conditions rather than
(for example) silently corrupting data. 

I do agree that hanging the entire machine is another story altogether:).