[Mimedefang] Regexp help

Paul Murphy Paul.Murphy at argentadiscovery.com
Thu Feb 21 09:17:19 EST 2008

> We had to allow literal helo in correct format in private IP space,
> after a few problem reports.  In some local network configuration that
> I won't pretend to understand, the mail server is in a private network
> and its outbound connections pass through a gateway.  We see the public
> IP of the gateway box, but the mail server only knows its private IP
> address.  If it says 'helo []' it is doing what it can.  This
> at any rate is the story I got from 3 or 4 system admins before I gave
> up on refusing for using private IP helo.

It should instead say "helo mail.xyz.com", and have the public DNS provide the public IP address in response to queries against that name.  If the reverse DNS also works and provides "mail.xyz.com", so much the better.

There really is no excuse for a private mail host advertising a private IP address on a public connection.


Paul Murphy
Head of I.T.
Argenta Discovery
Tel. 01279 645 554
Fax. 01279 645 646

Argenta Discovery Ltd, 8-9 Spire Green Centre, Harlow, Essex, CM19 5TR
Registered in England No. 3671653

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