From: scott@asd.com (Scott Barman)
Subject: Synchronous and asynchronous SCSI periphs under SunOS 4.1.*
Organization: American Software Development Corp., W. Babylon, NY
Date: Tue, 13 Oct 1992 19:31:44 GMT

This problem is on a SPARCstation 2, but I believe the model is not the
problem here.  I think it might be a problem with the operating system.
Please bear with me, I am a bit frustrated with this.

We upgraded from Sun 3/60s to SPARCs.  In the process we decided to keep
a 1.2Gb Wren 7 SCSI drive and an Archive QIC-150 streaming tape.  Both
run async SCSI (and do NOT require the ESDI-to-SCSI converter boards).
The system it is attached to has a 424Mb internal disk and a Sun CD-ROM.

When the system arrived, I installed 4.1.1.  I ran into a problem
getting the Wren 7 and tape drive to work with the system.  The boot
time autoconfig saw the SCSI controller (esp0) and hung after that.
After long phone calls to Sun I contacted a friend who was an SE and
told me what to do to the kernel configuration to turn off the Global
Synchronous capability.  OK, so I was running 1 Mbit SCSI and not 4 Mbit
SCSI, but I have 1.2Gb of disk space, which is important.

I complained to Sun (a lot good this does).  After another round of long
phone calls and email (some of them accusing me of not knowing what I
was doing after 10 years of this balloney) they told me that both
devices SHOULD work on the SCSI bus.  They questioned *everything*
including the cable length (which *is* within specs) and bus
termination (it is).  Instead of saying they did not know, they accused
me of not installing things correctly.  I offered to let them send me a
local tech to check for themselves.  Finally, they told me to forget it,
it was a relativly known problem and it would be fixed in the future.

Well, the future is now!  After a paperwork SNAFU (Sun's) we received
the 4.1.2 upgrade about the same time we received the 4.1.3 upgrade. 
This past weekend I finally got a chance to make the upgrade.  After
getting 4.1.2 loaded I tried to reboot the SS2.  It hung after the
autoconfig sensed the SCSI controller.  It took me a while to remember
what happened in the past.  I removed the cable to the disk and tape
(just shutting off the power did not work!), terminated the bus at the
CD-ROM drive, booted the system, found the place to make the change and
recompiled the kernel.  Now there's no problem but we are running async
SCSI only on a system with the primary database server whose swap area
is on a disk that *could* run synchronous SCSI and doesn't.

After someone from Sun (in the past) told me that Sun has "improved"
the service on the 800 number, I just tried to call them.  I haven't
told them about this because I hung up after 10 minutes of being on
hold!  I want to ask Sun why I can't run both sync and async SCSI
peripherals on the same bus eventhough Sun engineers have told me I
could.  Also, I want to know why the SCSI driver can't sense that there
are async SCSI devices on the bus and not hang?  Why do I have to modify
the autoconfig.h in /usr/kvm/sys/scsi to tell it not to check for sync
capabilities?  Why can't the driver figure it out for itself?

I also want to know if this is still a problem in 4.1.3 (which I will
upgrade to soon)?  Do I have to make these mods there too (I see nothing
about this in their documentation)?

What about Solaris 2.0?  Does someone have the early access versions and
can tell me about their drivers?  I know kernel configuration has
changed under Solaris 2, but I am worried about not being able to make
this mod and losing my 1.2Gb of disk space!

Is Sun listening?
-- 
scott barman			| <This space intentionally left blank>
scott@asd.com			|
 (I can barely speak for myself, you expect me to speak for my employer??)
Newsgroups: comp.sys.sun.misc