I have a nasty double NAT problem because I have two routers, one is my Archer C6 with OpenWrt installed, and another one is a proprietary router from my ISP which has a Fibre-to-the-Home optical cable connected to it, obviously I can't remove it and plug it directly into my Archer.
So instead I found out that I can use "bridge mode" to totally disable NAT on the ISP router, so that all requests would be forward to my router.
I was able to access the ISP router's web control and used it to switch it to bridge mode. Now the issue is that I don't know how I should configure the "WAN" interface, what protocol should I use? I tried DHCP, PPP, PPPoE and Static but none of them worked
Thanks for the help in advance!