Re: [Exim] Verisign pulls a fast one

On Thu, Sep 18, 2003 at 01:22:24AM -0700, Avleen Vig said:
> On Wed, Sep 17, 2003 at 07:16:03PM -0400, Walt Reed wrote:
> > Many mail servers fall back to the A record when no MX exists.
> > BTW, anyone have an ACL that rejects mail when the sender envelope
> > domain does not have a valid MX record?
>
> I wouldn't recommend this. It's perfectly legal for DNS zones to not
> have MX records and still send and receive mail.
> An MX record simply allows you to have a smaller set of hosts receive
> all mail for that zone, instead of each individual machines receiving.

... which is one of the reasons (probably the largest) that wild-card
records were created in the first place! I just did a quick check of
about 2 years worth of mail archives. NONE of my non-spam mail was
missing MX records. What is technically correct, and what is commonly
accepted practice are two different things. I reject mail all the time
that is technically correct yet fails my (and spamassasin's) more
stringent criteria.