DDNS & VPN on ASUS TM-AC1900 router behind Pace 3801HGV RG?
I recently obtained an ASUS TM-AC1900 WiFi router. This dual-band router has several advanced features, including USB printer and file server, DDNS and VPN (PPTP & Open VPN) servers. I formerly had a WRT65G running DD-WRT.
My issue has to do with the DDNS and VPN configuration. The VPN will not set up unless the DDNS is set up first. The DDNS refuses to set up because the router's WAN address is in a private range (e.g. 192.168.2.1). Now, on a normal DSL or cable modem it would be no problem to place the modem into straight-through mode, where the public IP (e.g 108.76.143.X) shows up at the router's WAN port. But this does not seem to be an option on the Pace 3801HGV. There are some settings I don't understand under Link Configuration, having to do with "Supplimentary Network", "Cascaded Router", etc. but I'm not sure how to use those.