Author: Always Learning Date: To: Exim Subject: Re: [exim] End of the DNS MX record ?
On Tue, 2014-09-02 at 10:50 -0400, Chris Siebenmann wrote:
> They aren't redundant but they aren't necessary. The standard is that
> you try the A record[*] if there is no MX record.
>
> (This behavior is actually sometimes annoying, because it means that
> there is no clean standards-compliant way of saying 'this machine exists
> but you should never attempt mail delivery to it'. People often use
> various bogus MX values for this purpose, like 'MX localhost.' or 'MX
> .'.)