How-To Set Up with Uverse Gateway with Airport Extreme
As I was trying to setup BTMM, I got a "double NAT" error. To use BTMM, you have to use either Time Capsule or Airport Extreme, so that NAT has to be enabled. That meant I had to figure out how to turn off U-verse's. I looked through the settings but saw nothing about it. Several hours of research--and a useless support call to AT&T--I finally figured it out. Here's the configuration you need, in brief.
On the Airport Extreme, under Internet > Internet Connections, Connection Sharing must be set to "Share a public IP address". Then under the NAT button, Enable NAT Port Mapping Protocol must be checked.
Now, unless you doe rest of this configuration, you will get a double DHCP error. So, in the Uverse Gateway settings, you must do this:
1. Under Wireless, click the option to DISABLE wireless. Click Save.
2. Under Firewall, click the option with DMZ in the name. On this page, choose your Airport Extreme (whatever you named it). Then scroll down and choose the option that says "Allow All Applications (DMZPlus Mode)". Save that configuration. DO A HARD RESET ON THE AIRPORT EXTREME. Then that should enable a single NAT protocol and BTMM will be on its way. And your wireless network will be set up properly.
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