Path: utzoo!utgpu!jarvis.csri.toronto.edu!me!radio.astro!helios!root
From: root@helios.toronto.edu (Operator)
Newsgroups: comp.misc
Subject: Re: How do I connect a DEC DELNI to a thin-wire Ethernet?
Message-ID: <810@helios.toronto.edu>
Date: 25 May 89 19:58:54 GMT
References: <2987@crete.cs.glasgow.ac.uk>
Reply-To: sysruth@helios.physics.utoronto.ca (Ruth Milner)
Organization: University of Toronto Physics/Astronomy/CITA
Lines: 37

In article <2987@crete.cs.glasgow.ac.uk> shoat@cs.glasgow.ac.uk (Mr. David Shoat) writes:
>
>What's the best (only?) way to break out from a DEC DELNI onto thin-wire? 

Just buy a thinwire transceiver, an in-line type that you insert into the
RG58 and which has the standard transceiver cable connector on the other
side. Then you plug your DELNI into it with a transceiver cable.

>Does anyone know why my whole damn network crashes every time I throw the
>switch on the DELNI which enables the external port?
>

Enabling the external port sends all packets from any of the equipment plugged 
into the other ports out through it onto the coax connected to it. Since you 
presumably don't have a coax there (judging by the above question), the packets 
are going off into never-never land, and as far as the equipment is concerned,
the network is dead.

If you don't have a coax (or thinwire) connected, there is no reason at all 
why you would need to enable the external port. This is the point of the
switch - you can be isolated or not, as you choose.

A DELNI is essentially an ethernet-in-a-box. If *all* your network equipment
is in one place, and there's only 8 of them, you don't need to lay any
cable. (Actually you can get more than 8 by "cascading" DELNI's - nicely
described in the DELNI manual).

Remember, for the future, that should your real coax jam or break, you can
make your systems on the DELNI stay alive by flipping the switch to disable
the external port. We have found this to be extremely useful for our
VAXcluster, all the members of which are connected to the same DELNI.

-- 
 Ruth Milner          UUCP - {uunet,pyramid}!utai!helios.physics!sysruth
 Systems Manager      BITNET - sysruth@utorphys
 U. of Toronto        INTERNET - sysruth@helios.physics.utoronto.ca
  Physics/Astronomy/CITA Computing Consortium