Enabling bridge mode on AT&T U-verse

Although hard to find, bridge mode is fully supported on their 2Wire routers.

These are instructions to configure a U-verse gateway to send all of its incoming traffic to your own router without impacting its normal networking services.

The gateway

The gateway model that I am using is a 2Wire/Pace 3800HGV-B, but these instructions likely work for similar models.

You can connect to it at 192.168.1.254. This service is abysmally slow and fairly hard to navigate as a result. The gateway will on occasion prompt for the password labeled “system password” on its serial number sticker.

Turning on DMZplus

First, we need to forward all of the traffic to the router. This can be done as follows:

  1. From the gateway, navigate to: Settings > Firewall > Applications, Pinholes and DMZ.
  2. Choose the router from the list. It will appear as a link named “Choose <name>.”
  3. Change its setting below to “Allow all applications (DMZplus mode).”

Assigning a public IP

Finally, we need to give the router the knowledge that it’s a public-facing device. UPnP and NAT-PMP rely on determining the public IP, and having the correct WAN IP is required for many routers.

We can achieve this by assigning the router the public IP address as follows:

  1. Navigate to Settings > LAN > IP Address Allocation.
  2. Locate the settings box for the router.
  3. Change its “Address Assignment” from “Private” to “Public.”

All done

After the router renews its DHCP lease, it will be assigned the public IP address. This is generally a huge button labeled “Renew DHCP Lease” or a power cable plugged into the device.

U-verse IP addresses are dynamic, but are deterministic from hardware configurations on their end. Thankfully, this means the addresses very rarely change. I’ve gotten away with just adding an A record to a random domain name to make it easy to access my VPN.