msf1537@uxf.cso.uiuc.edu (08/01/88)
Today's question is brought to you from the offices of the Student Government
Association at the University of Illinois, which is having the problem I am
about to describe:
What is the best way to connect one hard drive to two Macs?
The setup in question is an Everex 20mb hard disk, currently hooked up to (and
used as the boot disk for) a Macintosh SE. There is another Mac SE not three
feet away, and the question has arisen as to whether or not both computers can
easily be hooked up to the hard disk.
Ideally, one would be able to sit down, turn on the hard disk, (let it warm up,)
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 second 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.
Can this be done, or will connecting the drive to two Macs mean giving it up as
a boot drive? If it can be done, what method will work the best?
Responses made by machine (notesfile or E-mail) must arrive before August 6th
if they are to reach me, as my account is closing. US Mail will work forever,
which is probably its only major advantage.
Scott Forbes | UUCP: uunet!uiucuxc!uxf!msf1537
Univ. of Illinois | Internet: msf1537@uxf.cso.uiuc.edu
at Urbana/Champaign |
| US Mail: 311 E. Armory
"Is this thing on???" | (after 8/6) Champaign, IL 61820lad@eplrx7.UUCP (Lawrence A. Deleski) (08/02/88)
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. uunet!eplrx7!lad | Engineering Physics Lab Cash-We-Serve 76127,104 | Wilmington, Delaware 19898 MABELL: (302) 695-9353 | Mail Stop: E357-302
kmw@ardent.UUCP (Ken Wallich) (08/04/88)
>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. > In article <625@eplrx7.UUCP> lad@eplrx7.UUCP (Lawrence A. Deleski) writes: [ >One way around this is using PhoneNet with TOPS. Actually I use LocalTalk cabling (it was cheap for me), but Lawrences' description is the way I did it too. I have my 128K->512KE "networked" with my Mac II, and they both run their applications off of the same hard disk. It is slow booting up, and some games won't work on the "old mac" accross Apple..., oops LocalTalk, but in general it works just dandy. Hooking both macs to the same hard disc off of their SCSI ports is a no-no. The only big problem is that you cannot run the same application on both machines off of the same hard disc at the same time. Works fine if you make a copy of the application, and run that, but you can't open the same application twice. -- * any ideas expressed herein are pure coincidence and do not reflect reality * Ken Wallich Work: kmw@ardent.com Home: dworkin@amber.UUCP Ardent Computer Corp hplabs!ardent!kmw ubvax!amber!dworkin Sunnyvale, California, USA "He distinctly said 'to blave'"
hallett@armstrong.steinmetz (Jeff A. Hallett) (08/05/88)
In article <625@eplrx7.UUCP> lad@eplrx7.UUCP (Lawrence A. Deleski) writes: >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] > >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. The only problem with this is that everytime the second Mac accesses the mounted drive, the first Mac pauses. This is a function of the "single-user" mode of Macintosh hardware. If you plan on having this drive mounted on several Macintoshes, you're better off dedicating a Mac and a drive and using AppleShare because the net effect will be the same - the mounted Macintosh will be unusable. We ran across this the hard way. Now, we have TOPS on a net with >6 Macs on it, linked to several zones via Kinetics pathboxes with one Mac serving an 80Meg AST. The published Mac is password protected so only our group can mount it, but the speed degradation is quite noticable. Jeffrey A. Hallett | ARPA: hallett@ge-crd.arpa Software Technology Program | UUCP: desdemona!hallett@steinmetz.uucp GE Corporate Research and Development | (518) 387-5654 +--------------------------------------+--------------------------------------+ | "Isn't fun like the best thing to have ever? | | - Arthur | +-----------------------------------------------------------------------------+