I have my Ooma Telo (old version, the one with touch buttons) setup as follows
I have my routers WAN port set to static IP 172.27.35.8 and OOMAs LAN IP at the default of 172.27.35.1. I then set the DMZ on OOMA to 172.27.35.8. With this setup, I can connect to the VPN server on my router from the internet with no problems.
I have the exact same setup with my Dad’s OOMA, but he has a newer Telo, the one with the mechanical buttons. I cannot successfully VPN into his router. He does have a different router, but I don’t think it’s the router’s problem because if I take away the OOMA and have the cable modem connected directly to the router, I can VPN in just fine.
This is all PPTP VPN by the way.
I’m suspecting it’s something in the newer Telo firmware that is blocking this, but I’m not certain. Besides moving the OOMA to connect to one of the LAN ports of the router, does anyone know what might be the problem or have any suggestions to connect to the VPN server successfully?