convention for MX records

[Will Yardley]

Bob Zachok wrote:
 
> Is this an acceptable way of setting up DNS for a domain?  Their ISP
> seems to think so.  I got into a strong discussion with their DNS
> administrator, because I felt that MX records should accurately
> reflect the actual mail exchangers.  Obviously, he disagreed.

my understanding is that this is just fine. for instance in many cases
you'll want to have one mail exchanger as the gateway for all mail to a
domain or location.  obviously in this case you'd set the MX record to
point to the mail gateway(s); however these servers very well might
provide routing within an organization.

this isn't really a DNS specific question though - it's more a matter of
how you want to setup your mail servers.  there's no requirement that an
MX reflect the routing of mail (in fact often you _don't_ want it to
be).

so my opinion is that he's correct.  now if you were configured to be a
_backup_ for their primary mail server then you'd presumably want to be
listed as an MX with a lower preference.  however if you're the
_destination_ for mail and the other machine is the primary gateway for
incoming mail (which is what it sounded like from what you said), it's
better not to complicate things by adding you as a secondary MX.

w

-- 
GPG Public Key:
http://infinitejazz.net/will/pgp/