[Mimedefang] Revisit: Filtering on HELO

Les Mikesell les at futuresource.com
Mon Mar 26 12:59:23 EDT 2007

Philip Prindeville wrote:

> Web farms, VMware, etc. all throw whatever assumptions
> we had about multi-homing out the window.

There never were any correct assumptions, which is why the RFC says you 
can't reject based on your second-guesses.  Even if a server handling 
virtual domains has separate MX IPs for receiving mail, there is no 
requirement that it has to use corresponding IP or HELO name when 
sending - or that sending to other sites even be handled by the same host.

   Les Mikesell
    lesmikesell at gmail.com

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