HowTo - open port 80 to WAN for personal web server

[ros]

Prerequisites:
You have set your web server to run on port 81.


First move WebGUI (Asus administration interface) to some other port, for example 8080:

nvram set http_lanport=8080
nvram commit && reboot

Now edit /usr/local/sbin/post-firewall
and add following rule:

iptables -i ppp0 -t nat -I PREROUTING -m tcp -p tcp --dport 80 -j DNAT --to-destination 192.168.1.254:81

where ppp0 is your WAN interface (can be also vlan1)
and
192.168.1.254 is your router local IP.

EDIT - perhaps moving WebGUI to port 8080 is not even required. Just access web server from lan at port 81 and from WAN at 80. Haven't tested.