Path: gmdzi!unido!mcsun!uunet!munnari.oz.au!yoyo.aarnet.edu.au!
sirius.ucs.adelaide.edu.au!augean.ua.OZ.AU!idall
From: id...@augean.ua.oz.au (Ian Dall)
Newsgroups: comp.unix.ultrix
Subject: Decnet-tcp/ip gateway.
Message-ID: <1991May29.151258.19842@augean.ua.OZ.AU>
Date: 29 May 91 15:12:58 GMT
Sender: id...@augean.ua.OZ.AU (Ian Dall)
Organization: Electrical & Electronic Eng., The University of Adelaide
Lines: 24


We have a zillion Vaxes and one lonely DecStation. The DecStation has
Decnet and the decnet-tcp/ip gateway software (as well, of course as
tcp-ip). We also have some tcp-ip only X terminals.

What we want to be able to do is run DecWindows clients on the VMS
machines and have them use the X server on the X terminals. Is this
possible? We would very much prefer a solution which ran on the
DecStation rather than the VMS machines since we would have to get
rather a lot of licences if we had the VMS solution (unless one VMS
machine could act as a gateway).

It seems to me that this could be done two ways. One would be for the
DecStation to appear as multiple nodes (the extra nodes being pseudo
nodes for the X terminals). The other would be to have the X terminals
appear as extra displays on the Decstation. Of course, being possible,
and being implimented are two different things...


-- 
 Ian Dall           life (n). A sexually transmitted disease which afflicts
                              some people more severely than others.
   ACSnet: id...@augean.oz
 Internet: id...@augean.oz.au

Path: gmdzi!unido!mcsun!uunet!munnari.oz.au!manuel!tridge
From: tri...@anu.oz.au (Andrew Tridgell)
Newsgroups: comp.unix.ultrix
Subject: Re: Decnet-tcp/ip gateway.
Message-ID: <1991May30.044852.20043@newshost.anu.edu.au>
Date: 30 May 91 04:48:52 GMT
References: <1991May29.151258.19842@augean.ua.OZ.AU>
Sender: n...@newshost.anu.edu.au
Organization: Australian National University, Canberra, ACT, Australia
Lines: 40

I installed the decnet internet gateway (comes with the decnet stuff in
Ultrix) and have found it works like a charm. It allows our PC's to
appear as extra displays on our decstation (our PC's have a decnet based
X package - PC DecWindows). We can do the same for vaxes or whatnot.
Basically the gateway makes a decnet node appear like aerodec:N where
you can make N any display number you like.

The source and binaries for this gateway is in 
/usr/examples/decnet/gatethru/ on our system (Ultrix 4.0 on a DS3100).
We added these lines to out /etc files

/etc/inetd.conf:
tba4-X11-display0	stream	tcp	nowait	
/usr/examples/decnet/gatethru/gatewayd gatex -dnet tba4 X$X0

/etc/services:
tba4-X11-display0	6002/tcp		# X11 server on tba4::0.0
/usr/examples/decnet/gatethru/gatewayd


Note that tba4:: is the decnet node name of the real machine (my PC -
but could be any decnet machine running X).  The display becomes
aerodec:2 in this example (from the 6002 entry).  Also note that both of
the entries above are ONE line, I added the carriage returns so it could
be read. 

Performance is quite reasonable, considering the net load.  It means I
can display X clients from SUN's, Sequent's etc.  without installing
Decnet on them, which is a great boon.  It can also be setup to work in
the other direction, but I haven't tried (read the manual for
instructions)

Thanks to DEC for a great product!


--
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Andrew Tridgell                 CSLab, Research School of Physical Science
tri...@aerodec.anu.edu.au       Australian National University
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