From mboxrd@z Thu Jan  1 00:00:00 1970
From: Philip Craig <philipc@snapgear.com>
Subject: Re: DNAT pptp to windows machine
Date: Wed, 03 Aug 2005 16:25:02 +1000
Message-ID: <42F0633E.4020000@snapgear.com>
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	<01d001c597f2$246fe580$0100a8c0@newlife>
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Ming-Ching Tiew wrote:
> As far as I know, PPTP connection tracking is for the PPTP client going
> through firewall, ie pptp masquerade. It is not needed for DNAT of PPTP 
> into a pptp server.

The PPTP connection tracking works for both clients and servers,
since after all, you need one of each to make a PPTP connection.

While you can get by without it for DNAT to a server, the PPTP
connection tracking allows you to automatically NAT the related
GRE connections, and you can use a conntrack state match to only
allow related GRE packets through the firewall.