[ On Monday, April 1, 2002 at 21:51:36 (+0200), Dan Evans wrote: ]
> Subject: Re: [Exim] Refusing mail because of missing MX record
>
>
> I'd doubt it. There is no requirement in any of the RFC's that an MX records
> exists. If there is no MX, then an MTA will send to the first A record it
> finds, preferably the domain itself.
There "SHOULD" be an MX for the domain in the SMTP envelope sender
address, and in practice there almost always is. (An extremely small
number of really ancient sticks-in-the-mud throw-backs still refuse to
use MX records where they believe a normal hostname is sufficient.)
However there's no need for there to be an MX for the other hostname
used by the client-SMTP, i.e. the one used in its HELO/EHLO greeting.
There usually is one though except in the more rare cases where the
given host is used only for outgoing SMTP connections and where its own
hostname bears no relation to the e-mail domains used by its users.
--
Greg A. Woods
+1 416 218-0098; <gwoods@???>; <g.a.woods@???>; <woods@???>
Planix, Inc. <woods@???>; VE3TCP; Secrets of the Weird <woods@???>