[nsd-users] Hi! Im trying to set forward and reverse on an internal ip with nsd/unbound.

[Jamie Landeg-Jones]

tmberg via nsd-users <nsd-users at lists.nlnetlabs.nl> wrote:

> >> I want it to look like:
> >>
> >> Received: from [tMbERG_tMbERG_.224.starka.st] (tMbERG_tMbERG_.224.starka.st [tMbERG_tMbERG_.224.starka.st])
> >>          by mx.starka.st (mx.starka.st) with ESMTP id C46691BA5C
> >>          for <test-pu6fpd2ay at srv1.mail-tester.com>; Thu, 31 Jul 2025 17:48:33 +0200 (CEST)
> >>
> >> When sending mail. ( for example )
> >>
> >> Instead of:
> >>
> >> Received: from [192.168.0.224] (tMbERG_tMbERG_.224.starka.st [192.168.0.224])
> >>          by mx.starka.st (mx.starka.st) with ESMTP id C46691BA5C
> >>          for <test-pu6fpd2ay at srv1.mail-tester.com>; Thu, 31 Jul 2025 17:48:33 +0200 (CEST)
> >>
> >> But can it be done?

> Sorry. I forgot to mention that Postfix/Unbound/Nsd is running on the 
> same box.
>
> Since its the same box I was thinking. Its all originating from the same 
> system. It could be "fun". And because I can. ( Well... )
>
> Setting it like that.
>
> Thats it!

The standard "from" part of the header is either:

Received: from HELO-STRING (HOSTNAME [IP-ADDRESS]) by ....

or:

Received: from HELO-STRING (IP-ADDRESS) by ....

So, it seems like your reverse DNS is fine, but your mail client isn't
sending the correct "HELO" string.

Also, you can't avoid the IP address appearing unless you reconfigure
postfix itself to behave in a  non-standard way:

https://serverfault.com/questions/952009/how-to-modify-receive-header-in-postfix

https://www.pobox.help/hc/en-us/articles/1500000193602-The-elements-of-a-Received-header

So, you just need to fix your mail client!

P.S. "HELO" string can also be "EHLO" string, and is basically the client greeting.

Cheers, Jamie