From: leonardz@sgi2 ()
Newsgroups: comp.sys.sgi
Subject: Re: Multiple ethernets & serial ports on indigi ??
Date: 5 Oct 1992 22:24:23 GMT
Organization: Department of Mathematics & Statistics, Univ. of Guelph
NNTP-Posting-Host: sgi2.mathstat.uoguelph.ca
X-Newsreader: TIN [version 1.1 PL6]

	Based on Dave's reply below, 
1)	2 ethernets are not available now, but may be soon.
2)	multiple serial ports are not available now, but may be avialble soon
	Mark Bartelt points out that a SCSI connected device may do the job,
	but has no pointers to a source. 

Dave Olson (olson@anchor.esd.sgi.com) wrote:
: In <BvHzwt.Ayz@helios.physics.utoronto.ca> sysmark@helios.physics.utoronto.ca (Mark Bartelt) writes:
: 
: | [ Len Zaifman ]
: | 
: | |     A colleague at a nearby university is buying a Sparc server because
: | | he needs two ethernet connections  and up to 8 serial connections. He
: | | claims this cannot be done cost effectively, if at all, on an Indigo. Is
: | | this correct?? How much would an extra ethernet board and a port serial
: | | I/O board be for an indigo?? Are they even available ??
: | 
: | Dunno about how to deal with the need for a second ethernet, but there are
: | a couple companies around which make multiport serial devices that live on
: | the SCSI bus.  However, I've heard strongly conflicting reports about how
: | well these things work.  Caveat emptor.
: 
: It is certainly true today.  There has been occasional talk of doing
: an ethernet board for the Indigo to fit in the GIO slots, but I don't
: know if this is an official project or not.
: 
: Serial ports are a problem.  We looked at doing the SCSI serial port
: product from Central Data, and may do it some day; it is unlikely that
: anybody but us could make it work with our streams tty stuff.
: 
: Another option for serial ports is one of the cheap ethernet terminal
: servers.  They can be had for around $1500 US, from what I remember.
: Just how hard they might be to set up and make work I have no idea,
: but at least it is feasible.
: --
: Let no one tell me that silence gives consent,  |   Dave Olson
: because whoever is silent dissents.             |   Silicon Graphics, Inc.
:     Maria Isabel Barreno                        |   olson@sgi.com


	Based on the lack of an integrated solution, I used an idea
proposed by one correspondent who suggested terminal servers.

	I sent the following to my colleague. It would be useful, if someone
can see a better solution, as I am a bit leary of  the eperformance of the
pc bridge.

...
 thought about your problem  regarding a compute server with
two ethernets and multiple serial ports. You can solve both problems
with a system that has only a small number of serial ports and only
1 ethernet interface:


1)  get your computing services to sell you a redundant terminal server.
    The serial connections are made to it , and the connection to the
    compute server is via an ethernet.

2)  get a spare pc , no screen or hard disk needed, with two ethernet
    cards and run pcroute , a PD package to route between two networks.
    cost, excluding a pc is just the cost of 2 network cards (~ 350.00).
    If most traffic is on astronet , and not on physics net this works
    well.


    So your network would look like this:

	    Physics net
    ____________________________________________________________
				    |
				    |
			    ________|___________
			    |			|
			    | astro bridge	|
			    |			|  << pc running
			    |___________________|     pc route
				    |
				    |
				    |
		Astro net	    |
    ________________________________|________________________________
		|					   |
		|					   |
	________|____________			___________|________
	|		    |			|		    |
	|   astro terminal  |			|   astro compute   |
	|	server	    |			|	server	    |
	|___________________|			|___________________|

	terminal serial interfaces

    Hope this gives you other options to explore.

Newsgroups: comp.sys.sgi