Fwd: [ILUG] [OT] Smart Telecom Broadband offer?

[conor.daly at cod.utvinternet.com]

On Thu, Feb 24, 2005 at 02:03:43PM +0000 or so it is rumoured hereabouts, 
Michael Thompson thought:
> 
> On Demand Mail Relaying (ODMR) to collect your email and deliver it to
> your local mail server. ODMR is supported by fetchmail and means you
> can keep your mailserver behind a firewall with a dynamic ip address,
> but still have the correct envelope addresses when the mail is
> delivered to your local mail server, very handy.

So, this looks like the option to use via dyndns.  I've set up an exim
server in my DMZ.  It has no inbound access to my LAN.  Inside the LAN is
a postfix server listening to localhost:25 and nothing else.  It uses my
ISP's mailserver as its smarthost.  Mail collection is currently done with
POP from various public pop servers.  It looks like I can do ODMR between
these two hosts (http://www.plonk.de/sw/odmr/) using fetchmail.  Esr's
fetchmail manual (http://catb.org/~esr/fetchmail/fetchmail-man.html#14)
says:
	"In ETRN and ODMR modes, fetchmail does not actually retrieve
	messages; instead, it asks the server's SMTP listener to start a
	queue flush to the client via SMTP."

Now, the main question here is:  Do I need to open port 25 from DMZ to LAN
to allow this to work?  Jokob Hirsch suggests not...

BTW, what tests can I do to check that I'm not running an open relay?
Exim is setup using eximconfig (http://www.jcdigita.com/eximconfig/)

Conor
-- 
Conor Daly <conor.daly at oceanfree.net>

Domestic Sysadmin :-)
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