From: davecb@nexus.yorku.ca (David Collier-Brown)
Subject: Re: Microsoft Mail SMTP Gateway
Organization: York University
Date: Thu, 7 Jan 1993 14:31:44 GMT

mikebo@i88.isc.com (Michael Borowiec) writes:
|If anyone has gone the MS-MAIL with SMTP gateway route, I'd be 
|interested in your experiences so far. Especially...

|1) How hard it is to get/keep the gateway configured?
	For a small number of people, fairly easy.  We have
	an experimental (proof of concept) service for our
	own department. We have some 103 people, of which
	13 have their mail redirected to a MS-MAIL post office
	from the ccs.yorku.ca mail nail-server.

	Registration has to be kept in sync manually, so we simply send mail
	to each other when someone changes.  This is perfectly possible for
	13 people, scales badly for 100 people and is probably the
	definitive bad idea for the whole staff (we have about 16,146
	mailboxes for non-students at last count: lord knows how
	many undergrads we have)
.
|2) Do MS-Mail postoffices require an additional and expensive
|   "downstream" module to route or send SMTP mail to the gateway
|   or to translate MS-Mail to Internet style addresses? A Microsoft
|   rep has claimed the SMTP gateway package is all we need.

	I'll have to ask...

|3) MS-DOS is single tasking, I assume one SMTP connection at a time?
|   Does this create real problems? What are they?

	Well, the queue gets long (:-))  We  process 150-200 K messages
	a month (that's only 5,000 - 6,000 per day) so a single
	gateway wouldn't work for a large configuration.  Assume the
	delivery rate and processing rate aggregate to about one message
	per 30 seconds and we'd need something like 3 gateways.  As
	messages get larger or the arrival times get lower, the
	need would go up, of course.

|4) Any problem with the gateway wedging up? If so, any workarounds?

	Yup: don't use a PC.  We had a amchine that was too small
	initially and it hung due to an out-of-memory problem
	with some regularity.  Throwwing hardware at it fixed the
	problem.

|5) Can you have multiple SMTP gateways on one LOCAL Area Network?

	As I understand it, the number of gateways is mostly
	a naming issue: some machine gateways for a given
	named aggregate (in our case ``ccs'').  We are going
	to see if we can add a second community to the same gateway
	Real Soon Now (:-)).

|6) Can you have multiple SMTP gateways on one WIDE Area Network?

	Yup.

|7) If yes to 5 or 6, how do you route mail to the correct gateway?

	On a per-domain or per-person basis, accept the mail at an
	intermediate machine and route there. We use zmailer and
	can route domains via a ``routes'' override file and
	people via a normal alias file.  If you use sendfail(8)
	you'd best use aliases.

	In general, a community is going to have more than one
	``religion'' of mailer, and you will have to do the 
	following as a general (and also worst) case:

	for each in named-communitys; do
		find sysadmin*2, novell server, nlm, \
			pc, gateway software, unix server;
		register all users at each end
		coordinate aliases between gateways
		while :; do
			for day in workdays; do
				monitor
				amend
			done
		done
	done

	Not too different from managing our old PROFS system.

--dave
-- 
David Collier-Brown,  | davecb@CCS.YorkU.CA | lethe!dave
72 Abitibi Ave.,      | 
Willowdale, Ontario,  | York Postmaster and
CANADA. 416-223-8968  | occasional sendfail(8) consultant.