Path: utzoo!attcan!utgpu!jarvis.csri.toronto.edu!cs.utexas.edu!uwm.edu!psuvax1!ehrlich
From: ehrlich@cs.psu.edu (Daniel Ehrlich)
Newsgroups: comp.mail.sendmail
Subject: Re: Dealing with Subdomains
Message-ID: <1989Dec6.155241.29644@psuvax1.cs.psu.edu>
Date: 6 Dec 89 15:52:41 GMT
References: <5565@ncar.ucar.edu>
Sender: ehrlich@psuvax1.cs.psu.edu (Daniel Ehrlich)
Organization: Computer Science Department, Penn State University
Lines: 34
In-Reply-To: woods@ncar.ucar.edu's message of 5 Dec 89 21:53:13 GMT

In article <5565@ncar.ucar.edu> woods@ncar.ucar.edu (Greg Woods) writes:

Greg> We are about to split our domain up into subdomains, and I am trying to make
Greg> the necessary changes in the sendmail configuration to account for this. In
Greg> particular, I want to make it unnecessary for users in one subdomain to
Greg> fully qualify every name when sending mail to a host in a different subdomain.
Greg> I'd like it to work the way all the other applications (e.g. telnet, ftp,
Greg> rlogin) do. I can say

Greg> telnet host.sub

Greg> (i.e. as opposed to telnet host.sub.ucar.edu) and the resolver happily finds
Greg> the right host. So I would like to also be able to send mail to user@host.sub
Greg> and have it work. By adding this rule in ruleset 3

Greg> R$+<@$+>$*	$1<@$[$2$]>$3

The easiest way I know of to do this is have CNAME records in the outer
domain UCAR.EDU that point into the subdomain.  Something along the lines
of:

	$ORIGIN	ucar.edu.
	host	IN	CNAME	host.sub

in the name server files for ucar.edu would do.  This means that even though
you have sub-domains the host names must still be unique across all of
ucar.edu.

--
Dan Ehrlich <ehrlich@cs.psu.edu>
Quote of the month:
"And I have quite a bit of experience on mainframes.  I learned C, Pascal,
and Assembler on various mainframes, including PDPs, VAXen, an IBM AS/9000."
	-- Charles M Hannum II <cmh117@psuvm.psu.edu>