Ok, first off I admit i am addicted to this game NWN.
Now I have a RH7.3 gateway with two nic cards. One is connected to my dsl modem, other is my internal LAN card.
I want to have the gateway host NWN games which uses udp on port 5121.
I have the firewall_2.4_strong ruleset from the HOWTO running.
I have tried adding the PREROUTING and FORWARDING rules for port fowarding as in a WWW server, but no dice. I can connect to the game via LAN or via the public IP address, but no one else can.

HEre are the latest rules i tried, maybe someone can shed some light...
#NWN server forwarding
$IPTABLES -A FORWARD -i ppp0 -o eth1 -p udp --dport 5121 \
-m state --state NEW,ESTABLISHED,RELATED -j ACCEPT

#NWN SERVER port fowarding
$IPTABLES -t nat -A PREROUTING -p udp -d $EXTIP -j DNAT --to 192.168.1.1:5121

this is the order in which the rules appear. I am not clear on what the order should be...
192.168.1.1 is my gateway LAN address..

Thanks
Andy

if the server is also the internet firewall then you should not need to forward any ports.

Is it another machine behind the firewall?

OK, so does this mean I do not need any rule set?

you will need to have rules to open the ports used if it is firewalled.

The game you are running will open ports to listen on and it should work ok.

Port forwarding would be need if you are hosting a game behind a firewall router, the ports would need to be forwarded to the game host.