Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!uflorida!ukma!xanth!ames!elroy!gryphon!jdow
From: jdow@gryphon.COM (J. Dow)
Newsgroups: comp.sys.amiga
Subject: Re: SCSI question
Summary: Yup - but can be abused...
Message-ID: <12889@gryphon.COM>
Date: 4 Mar 89 07:56:49 GMT
References: <EY0TW=y00WB9I=GUlN@andrew.cmu.edu>
Reply-To: jdow@gryphon.COM (J. Dow)
Organization: Wizardess Designs, Hermosa Beach, Ca.
Lines: 37

In article <EY0TW=y00WB9I=GUlN@andrew.cmu.edu> rg20+@andrew.cmu.edu (Rick Francis Golembiewski) writes:
>I seem to remember a reading somewhere that 2 machines with SCSI
>controllers could be hooked up to the SAME hard drive (with
>partitions for each if the machines used a different format).  Has
>anyone tried something like this?  I was kind of wondering if would
>be possible to hook an Amiga with SCSI controller up to a Mac's
>external HD.  Kind of a crazy solution, but the other alternative
>requires $$$ for a HD (sigh...).  Any comments are appreciated.
Yup, you can. With HardFrame, for example, you could set the two controllers
to separate SCSI addresses and have both connect to the same drive. But what
you cannot do in that situation is have both of them autoboot. (They'd try
to mount the same partitions. While this is not "impossible" and CAN run  it
results in corrupted filesystems REAL fast unless you use REAL weird disk
change tricks. (I have a disked script that seems to work. Argh is it a
crungy hack so I won't tell anyone how.))

Now as far as hooking to a Mac's port I really dunno. I have heard that MacSCSI
is not a real SCSI in that there are large parts of the protocol that are not
supported. It'd be particularly dangerous if MacSCSI does not support the SCSI
arbitration cycle. This is semi-optional as you are allowed to design a bus
controller that assumes it will not have to arbitrate because it is the only
controller on the bus.

If ya hook it up and try it let us on the net know how it works! Most all of
the A/B2000 controllers should work on the Amiga end. WHo knows re Mac end?

-- 
Sometimes a bird in the hand leaves a sticky deposit.
Perhaps it were best it remain there in the bush with the other one.

{@_@}
	jdow@bix (where else?)		Sometimes the dragon wins. Sometimes
	jdow@gryphon.CTS.COM		the knight. Does the fair maiden ever
	{backbone}!gryphon!jdow		win? Surely both the knight and dragon
					stink. Maybe the maiden should suicide?
					Better yet - she should get an Amiga and
					quit playing with dragons and knights.