Path: utzoo!utgpu!attcan!uunet!eplrx7!lad
From: lad@eplrx7.UUCP (Lawrence A. Deleski)
Newsgroups: comp.sys.mac
Subject: Re: Network!?  What's that?
Message-ID: <625@eplrx7.UUCP>
Date: 2 Aug 88 14:32:34 GMT
References: <46700045@uxf.cso.uiuc.edu>
Lines: 35

From article <46700045@uxf.cso.uiuc.edu>, by msf1537@uxf.cso.uiuc.edu:
> What is the best way to connect one hard drive to two Macs?
> 
[stuff deleted]

> Ideally, one would be able to sit down, turn on the hard disk,
> turn on either one of the Macs and have it boot from the hard disk.  Then, a
> second person would come in, turn on the 2nd Mac, and also boot from the hard
> disk, with both persons writing and reading to the hard disk (possibly even to
> the same application) at the same time.

All standard SCSI hard drives can only act as a single-user drive.  While
you can change the address of the SCSI disks,  (well,  some of them anyway),
the macs are all hard addressed at SCSI address 7.  If you tried to hook up
two Macs to a single SCSI disk the firstone might boot,  but turning on the
second Mac would lock up both systems and possibly result in damage to one
or both Macs,  and probably the hard disk too.

One way around this is using PhoneNet with TOPS.  The first Mac would be
connectd to the SCSI disk in the usual way.  The second Mac would connect to
the first Mac using a pair of PN connectors.  After booting the first Mac
and Publishing the HD with TOPS,  the second Mac could boot from a TOPS
startup floppy and mount the SCSI disk.  

This is not a fast as having a SCSI disk attached (in fact it's barely
faster than a floppy) but it beats having no HD at all.

Hope this helps.


-- 
        Lawrence A. Deleski         |       E.I. Dupont Co.
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