Path: utzoo!attcan!utgpu!jarvis.csri.toronto.edu!mailrus!cornell!uw-beaver!rice!sun-spots-request
From: jarsun1!jensen@uunet.uu.net (peter jensen)
Newsgroups: comp.sys.sun
Subject: SunOS 4.0.3 driver vs. Wren drives
Keywords: SunOS
Message-ID: <188@brazos.Rice.edu>
Date: 17 Jul 89 18:31:54 GMT
Sender: root@rice.edu
Organization: Sun-Spots
Lines: 75
Approved: Sun-Spots@rice.edu
X-Sun-Spots-Digest: Volume 8, Issue 74, message 9 of 18


	Apparent sc driver change causes timing problems with Wren drives:

We recently upgraded *one* of our machines from 4.0.1 to 4.0.3 to reassure
ourselves that this was a good thing to do.  Since the upgrade, the system
has "hung" eight times.  Here's the scoop:

	Hardware:
		Sun 3/50M-4 
		CDC Wren IV (94171-300) SCSI disk
		Exabyte 8mm cartridge tape drive
		Laserprinter

The system will boot and run fine for a few days and then hang, possibly
displaying the following message several times:

(This also happens without the Exabyte connected.  The SCSI bus is
properly terminated.)

	sd0:  sdtimer: I/O request timeout
		last phase= 0x4 (DATA IN)
		csr= 0xc407  bcr= 65535  tcr= 0x1
		cbsr= 0x45 (DATA IN)  cdr= 0x24  mr= 0x2  bsr=0x89
		target= 0, lun= 0  DMA addr= 0x3600 count= 2560 (8192)
		cdb= 8 6 7d ba 10 0

I had sent in a tape containing two crash dumps and talked to a CSC rep
several times about this problem.  This morning, I got a call from the rep
explaining that the problem was due to changes in the driver to optimize
it for faster disks.  The rep did acknolwedge that there is now a timing
problem with slower drives.

Sun's position on this is that Wrens (and Exabytes) are not supported
products, and customers should call Sun Consulting to BUY a new driver to
resolve the problem.  Personally, I don't feel someone should have to buy
a custom driver for a standard SCSI device.  Also, if Sun doesn't want to
support the Wren drives, they should remove the misleading information
from format.dat:

	# @(#)format.dat 1.20 89/03/26 SMI
	#
	# Copyright (c) 1987 by Sun Microsystems, Inc.
	#
	# Data file for the 'format' program.  This file defines the known
	# disks, disk types, and partition maps.
	#
		...
	#
	# This is the list of supported disks for embedded SCSI.
	#
	disk_type = "CDC Wren III 94161-155" ...
	disk_type = "CDC Wren IV 94171-344" ...
	disk_type = "CDC Wren V 94181-702" ...
		...

Unless Engineering starts receiving more bug reports about this problem,
they will not be doing anything to resolve the timing issue. 

FLAME ON

Aren't there enough {yp | nfs | network | compiler | your choice here}
bugs already, without needing to introduce additional problems?  We're
still waiting to get an NFS problem fixed - Is anyone else having problems
with their remote files getting corrupted (some bytes being replaced by
garbage or nulls)?

FLAME OFF

I hope other customers will place calls with CSC and show them how many
sites they're affecting with this driver BUG.  My service order number is
327515.

Peter C. Jensen     			          jensen@jarsun1.ZONE1.COM
Jordan Apostal Ritter Associates    ANSYS, ARIES, and Engineering Analysis
Admin Bldg 7, North Kingstown RI 02852    (401) 884-3014 or (401) 294-4589