Path: utzoo!mnetor!uunet!seismo!sundc!pitstop!sun!amdcad!ames!nrl-cmf!cmcl2!brl-adm!umd5!purdue!i.cc.purdue.edu!j.cc.purdue.edu!pur-ee!iuvax!bsu-cs!dhesi
From: dhesi@bsu-cs.UUCP (Rahul Dhesi)
Newsgroups: comp.unix.wizards
Subject: Re: Unix on a VAXCluster ??
Message-ID: <2225@bsu-cs.UUCP>
Date: 28 Feb 88 17:58:06 GMT
References: <985@luth.luth.se> <2359@umd5.umd.edu> <8309@eddie.MIT.EDU> <2369@umd5.umd.edu>
Reply-To: dhesi@bsu-cs.UUCP (Rahul Dhesi)
Organization: CS Dept, Ball St U, Muncie, Indiana
Lines: 20

>>>... What exactly does using VMS cluster hardware buy you ...

The VAXcluster is not an alternative to networking.  In fact most
VAXcluster installations also run DECnet at the same time.

A VAXcluster is essentially a number of CPUs having concurrent access
to a number of disk drives.  There is no communication between the CPUs
other than the availability of a cluster-wide lock facility, and the
ability to have batch jobs submitted from one CPU for execution on
another.  I may have missed one or two other minor things you can do
across CPUs.

To have interprocess communication between CPUs one uses DECnet,
which is rather clunky and slow, and not always secure.

One serious disadadvantage of a VAXcluster over Ethernet is that only
DEC-manufactured equipment can be easily used in a VAXcluster, thus
locking you into one product line.
-- 
Rahul Dhesi         UUCP:  <backbones>!{iuvax,pur-ee,uunet}!bsu-cs!dhesi