Re: reject mail if dns and rdns differ

[Dusan Obradovic]

> On Nov 11, 2019, at 2:27 PM, ratatouille <ratatoui...@bitclusive.de> wrote:
> 
> Hello all!
> 
> Received: from mail.namase.de (s1.bomberg.city [62.173.139.77])
> 
> I would like to reject incoming email if dns- and rdns-entries differ.
> Does this make sense and how could I achieve this?
> 
> Kind regards
> 
>  Andreas

Although it's a common occurrence that the host name specified in a HELO does 
not match IP rDNS (even from a well-known mail providers), you'd look into 
Postfix SMTP access policy delegation protocol to implement custom policy 
action based on helo_name and client_name. 
http://www.postfix.org/SMTPD_POLICY_README.html