Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!uunet!opel!johnk
From: johnk@opel.COM (John Kennedy)
Newsgroups: comp.periphs.scsi
Subject: Two HAs on single SCSI bus
Message-ID: <55@opel.COM>
Date: 17 Mar 91 21:31:00 GMT
Reply-To: johnk@opel.COM (John Kennedy)
Organization: Second Source, Inc., Annapolis, MD
Lines: 33

Are there any SCSI implementations available that allows use of two
host adapters on a single bus?  Specifically, I want to dual-port
a disk drive by such a configuration as this:


 ____________                                  ____________ 
|            |                                |            |
|            |                                |            |
|   CPU A    |           SCSI bus             |   CPU B    |
|            |================================|            |
|____________|              ||                |____________|
                           ____                             
                          (____)
                          |disk|
                          |____|

Is this what differential SCSI is? Is there any good published material on
the subject?

The goal is to have two redundant CPUs able to access the same data (not
necessarily at the same time, but that would be great).

I'm open to any advice.

Thanks,

John


-- 
John Kennedy                     johnk@opel.COM
Second Source, Inc.
Annapolis, MD