Re: Another Crazy DNS Question... ;-)

["Jens B. Jorgensen" <jjorgens@bdsinc.com>]

Bob Nielsen wrote:

> On Thu, Nov 04, 1999 at 12:01:29AM -0500, William T Wilson wrote:
> >
> > Yes, you can point A records from two domains to the same IP address.
>
> You can also use a CNAME record.  I'm not sure when one approach would
> be preferred over the other.

This is true however the rfc (not sure what number to look at) I believe says that the
hostname mentioned in an MX record shouldn't be a CNAME.

I should also mention that as far as how your mailserver appears to other machines,
when a mailserver is _sending_ mail out it first announces its identity via the HELO
or EHLO commands. What identity the host presents itself as to other SMTP hosts is
configurable in all the mail server packages I've dealt with. That said, mail server
packages that I've dealt with will only allow you configure it to present itself as a
single identity.

This doesn't affect mail clients which would get mail via POP/IMAP of course.

--
Jens B. Jorgensen
jjorgens@bdsinc.com