psi-jack@??? (Eric Renfro) [Friday, September 20, 2002 3:39 AM]:
> Hey, I'm wondering how I could get Exim4 to, by default, not allow
> non-reversable DNS entries, and also no MX entries in DNS, for all
> SMTP<->SMTP traffic, except authenticated users.
It is perfectly acceptable to have only an A and no MX record. In fact, if
you see most universities / large organizations where people have the option
of getting mail delivered to their own workstations rather than to the
university mailhub, all they need is an A record.
> After weeks of looking at why spam is marked as spam, I've pretty much
> figured that pretty much all that spam comes from non-reversable IP
> addresses.
Well, you won't really find that a reliable metric I think - but as you
please.
-srs