Re: [exim] Detect missing reverse dns

> From: "Ian P. Christian"

> > | Many small companies we work with haven's PTR records for
> > | IP-addresses of mail servers.
>
> If you're with a company that doesn't have control over your own rDNS,
> you should NOT be sending mail out onto the internet IMO, the chances
> are your ISP provides a relay for you to do this.

No, in such cases the monopolistic (former state) ISP don't provide a relay,
or the relay is in every blacklist. I repeat: they can't care less.

> We've had very few issues with blocking outright on rDNS

Don't conclude that everybody is like you.

> If all of
> us larger operators start being stricter, we can pretty much solve the
> botnet generated spam

Spammers already use webmails and stolen passwords more and more.
Blocking botnet generated spam is much easier - by means such as
greylisting (instead of denying) mail from hosts without rDNS.