From mboxrd@z Thu Jan  1 00:00:00 1970
From: Ivan Petrushev <ivanatora@gmail.com>
Subject: Re: Port forwarding
Date: Wed, 4 Feb 2009 20:38:09 +0200
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To: =?ISO-8859-2?B?QrNhv2VqIKZsdXNhcmVr?= <beju@beju.xon.pl>
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I think lots of people know how to forward ports.
Default policy doesn't concern you - it is DEFAULT. Once you add rules
that match the desired packets these rules do something and it is not
the default chain action.
Here is example port forwarding:
iptables -t nat -A PREROUTING -p tcp -d 192.168.1.2 --dport 27015 -j
DNAT --to-destination 192.168.0.34
iptables -t nat -A PREROUTING -p udp -d 192.168.1.2 --dport 27015 -j
DNAT --to-destination 192.168.0.34
And if your default FORWARD policy is DROP, then you should change it
to ACCEPT for the matched by the upper rules packets:
iptables -I FORWARD -d 192.168.1.2 -j ACCEPT