Path: utzoo!utgpu!jarvis.csri.toronto.edu!cs.utexas.edu!rice!sun-spots-request
From: mjacob@sun.com (Matt Jacob)
Newsgroups: comp.sys.sun
Subject: Re: More than one Sun on a SCSI bus
Keywords: Miscellaneous
Message-ID: <3264@brazos.Rice.edu>
Date: 17 Nov 89 06:30:28 GMT
Sender: root@rice.edu
Organization: Sun-Spots
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Approved: Sun-Spots@rice.edu
X-Refs:  Original: v8n197
X-Sun-Spots-Digest: Volume 8, Issue 206, message 2 of 15

Yeah, I actually tried this with a SS-1 && a 4/110.  If you have an SS-1,
here is what I did.

Patch the kernel to run no disconnect/reconnect (a lot of SCSI disks I've
run into get confused about accepting multiple commands from different
inititators). Procedure: as root,

	adb -w /vmunix
	scsi_options?W 0x10
	$q

Set the scsi initiator id for the SS-1 to something other than it's
default (7), e.g., as root,

	eeprom scsi-initiator-id=6

(halt, power on-off, or get into the forth monitor (n to the > prompt) and
enter reset).

You should be able to hook up another SS-1, or a 4/110 and run with both
of them seeing each other's disks, tapes, etc. Try to not have each system
boot or swap off the same partitions- madness results.  Ditto for mounting
partitions writable by each other- instant destruction.  It's a good way
for sharing read-only data though, and in the future with, say, a large
juke-box changer, a way for a couple of stations to access terabyte image
files, etc...