Portforwarding with pppoe won't work

Hairpin NAT

http://forum.mikrotik.com/t/hairpin-hat-not-working/113597/16

ip firewall nat
add action=dst-nat chain=dstnat dst-address=“your global IP” dst-port=443 in-interface=“LAN interface for your web server”
protocol=tcp src-address=“your LAN” to-addresses=172.20.0.100 to-ports=443
add action=masquerade chain=srcnat dst-address=172.20.0.100 dst-port=443 out-interface=“LAN interface for your web server” protocol=tcp src-address=“your LAN”