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Date: Wed, 3 Nov 2004 02:16:15 +0100
From: Erik Trulsson <ertr1013@student.uu.se>
To: John Fox <readbsd@mind.net>
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cc: freebsd-net@freebsd.org
Subject: Re: Simple port forwarding question
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On Tue, Nov 02, 2004 at 04:36:30PM -0800, John Fox wrote:
> Hi, folks.
> 
> I'm experimenting, trying to setup a situation where connections 
> to port 25 on machine A are forwarded to port 25 on machine B.
> I've read the ipfw manpage and it looks as though what I'm doing
> is correct.  
> 
> 
> The IPFW rules on machine A are:
>    00100 fwd machineB tcp from any to any 25
>    65535 allow ip from any to any
> 
> And there is a sendmail listening on B's port 25.
> 
> But when I telnet to machine A's port 25, all I get is
> a perpetual "Trying" message that just sits there.

Don't use "fwd" for this - it doesn't work that way (for one thing B is
unlikely to handle an IP-packet that is still adressed to A.)

Use natd and the '-redirect_port' option to natd instead - that works.




-- 
<Insert your favourite quote here.>
Erik Trulsson
ertr1013@student.uu.se