Re: Tracking source of outbound SMTP messages

[Ken Sims <mr3111@xxxxxxxxx>]

Hi Doug -

I see that you found the problem and that it was the AS/400 itself, but for 
future reference let me throw in a comment anyway ...

> >For example, your message (which  I'm replying to) contained this:
> >Received: from main (162-32.9-67.se.rr.com [67.9.32.162])
>
> And that is not my internal network address, it is my (current) IP cable
> address.  It wouldn't help me determine which machine on my network sent the
> message.

Your internal IP address does not show in what is quoted above because you 
are not using an internal SMTP server.  You are using your ISP's SMTP 
server which is external and which does not see your internal IP address.

BUT, if someone had been using the AS/400 as an SMTP server, the internal 
IP address would show on the first (lowest in the headers) "Received" line 
because the AS/400 is also internal and would see the PC's internal IP 
address.  The second "Received" line would show your company's external 
address as the AS/400 connects out to the recepient's SMTP server (or to a 
relay SMTP server if you use one).

Ken
http://www.ke9nr.net/
Opinions expressed are my own and do not necessarily represent the views of 
my employer or anyone in their right mind.