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How to setup IP Passthrough / Bridge Mode on Motorola NVG510 AT&T UVerse DSL Modem

Recently, my parents upgraded from AT&T’s old ADSL, to the new “UVerse” ADSL2+. With it came a new Motorola NVG510 UVerse all-in-one router / wireless access point / ADSL2+ modem combo. In my opinion, it’s routing and wireless abilities are total crap. Long ago I installed a Linksys WRT54G router that has been flashed with DD-WRT. This allows bandwidth monitoring, proper port forwarding, and also gives me the ability to connect via VPN remotely to help them out with problems on rare occasion. After their new Motorola UVerse modem was installed, my first order of business was to strip it of all routing and wireless functions, and make it just a router. On the old Novatel modems, this was called IP Passthrough, and pretty easy to set up. Now it’s changed and can take a little finesse to set up.

How to enable IP Passthrough on the Motorola NVG510 UVerse Gateway

I assume you already have a router to connect you NVG510 to. Go ahead and connect the routers WAN port to one of the LAN ports on the UVerse modem. You will need the MAC address of the WAN port on your router. You can usually find this on a sticker on the bottom of the unit. I’m going to pretend mine is AB:CD:EF:GH:IJ:KM for the scope of this article.

The router you are adding needs to have a LAN address that is not on the 192.168.1.x subnet. If you absolutely must have your router on that subnet, you can change the IP/subnet of the NVG510. If you need help with that, post in the comments and I would be glad to lend a hand.

With you computer connect to one of the LAN ports on the NVG510, navigate to the configuration page. By default it is You will see this page:


Now, click on the Firewall tab, then select IP Passthrough. You will need the password on the sticker, on the side of the NVG510 itself to login, unless you’ve already changed it.


Change the Allocation Mode to “Passthrough.”

The Default Server Internal Address should be set to whatever the temporary WAN IP address the NVG510 assigned to your router. After this is all done, your router will obtain your actual Public IP address, so don’t worry.

Passthrough Mode needs to be “DHCPS-fixed.” This tells the NVG510 to hand out your public IP to your router.

Passthrough Fixed MAC Address needs to be the MAC Address of the WAN port of your router (should be a sticker on the bottom of it) with colons used to separate each group, so it should be in this format: AB:CD:EF:HI:JK:LM

You can leave the DHCP Lease time set to defaults, or change it. It should matter either way.

Once you are finished, I would suggest disabling the UVerse Wireless on the NVG510 as that should now be handled by your router. To do this, select the Home Network tab and then select “Wireless.” Change Wireless Operation to “Off.”

Screen Shot 2015-05-02 at 6.47.13 PM

Now would be a good time to restart your UVerse DSL modem, and then restart your router after the modem has had a minute to boot up. If your mac address was entered properly, you should now be getting a WAN (Public) IP Address assigned to your router and the NVG510 will be in modem mode.

If you get stuck, feel free to ask for help. Good luck!