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NVG510 Bridge Mode???


NVG510 Bridge Mode???

Just switched from DSL (Motorola 2210) to UVerse (Motorola NVG510). I set the 2210 into bridge mode and ran my home network from an Apple Airport Extreme Base Station (AEBS). I have some complex configurations on my network and figured I'd be able to do the same thing with the NVG510. However, it seems the NVG510 uses different terminology than I am used to.


Under Firewall/IP Passthrough, I set:

Allocation Mode to 'Passthrough'

Passthrough Mode to 'DHCPS-Fixed'

Passthrough Fixed MAC Address to the AEBS' MAC address

And, I left the Lease at the default 10 minutes.


On the AEBS, under Internet/Internet Connection, I switched from 'PPPoE' to 'Ethernet'. I left the Ethernet WAN Port value at 'Automatic (Default)'. And Connection Sharing is set to 'Share a public IP address'.


This apparently is not enough, though. The AEBS reports that the "Wi-Fi base station does not have a valid IP address", and that there is a "Conflicting DHCP Range".


How do I turn off the DHCP on the NVG510? And, what are the correct settings to put the NVG510 into bridged mode?

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Message 1 of 90

Accepted Solutions

Re: NVG510 Bridge Mode???

A long post, but hopefully worth the reading:


I had some weird things happening the weekend after I set up my NVG510 as described above in the post starting:

"Okay, so here's what I've done that seems to be working at the moment...


- In the NVG510's setup, under Home Network, then Subnets & DHCP, I set the following:"


The Issue:

When family members were trying to access the Internet with multiple devices, things kept locking up. Say for example, the kids were trying to watch videos, one on an iPad, the other on an iPod Touch. The videos were buffering really slowly and kept locking up. So... back to the drawing board. Now, I have some interesting findings and a new setup.


The Research:

I researched IP-DSL and IP Passthrough a bit. It seems that IP-DSL, which U-verse is using, is actually using IP like a typical ethernet network. (Their prior DSL used ATM, which is a bit more complex technology.) The U-verse Residential Gateway (RG) is getting an IP address and gateway just like anything else you set up with IP and DHCP. The "Broadband IPv4 Address" on the Broadband Status tab is the public IP handed out to the RG. The "Gateway IPv4 Address" is the AT&T router managing the RG (typically called the "Default Gateway").


IP Passthrough is supposed to allow another device to receive the IP address of the RG. When IP Passthrough is turned on, then, the NVG510 is supposed to give its own public IP address to a specified LAN device. The instructions on the right-hand side of the IP Passthrough tab confirm this.


The Theoretical Setup

To set up the NVG510 correctly, then, for use with a home router (assuming you don't want to simply let your home router be a bridge, of course) -


Starting with the NVG510's default settings:


- Under Home Network, then Subnets & DHCP, I set the following:

Device IPv4 Address: <the IP address I want to use for the RG (the default is, which is okay too)>

DHCPv4 Start Address: <some IP address within the RG's subnet (say>

DHCPv4 End Address:  <the same IP address as the Start Address, above (since I'm not using the NVG510's DHCP)>


- Under Home Network, Wireless,

Wireless Operation: Off


- Under Firewall, IP Passthrough,

Allocation Mode: Passthrough

Passthrough Mode: DHCPS-fixed

Passthrough Fixed MAC Address: <MAC address of the home router>


On the AEBS, then:


- Under Internet, Internet Connection,

Connect Using: Ethernet

Connection Sharing: Share a Public IP Address


- Under Internet, TCP/IP,

Configure IPv4: DHCP


- Under Internet, DHCP, the DHCP values are set as normal, with an address range in a different subnet from the RG, though, in order to prevent double NAT messages. (For example, if the RG is 192.168.1.x, the AEBS is 192.168.2.x)


Restart the NVG510, then the AEBS.


Theoretically, the NVG510 should, using its own DHCP, give the AEBS its own public IP address (the "Broadband IPv4 Address"), a valid Subnet Mask, and the Default Gateway (Router) value equal to the "Gateway IPv4 Address".


In actuality, for some reason, the NVG510 only will give the AEBS its Gateway  and DNS values. The AEBS gets an internal IP address and a Subnet Mask of I suspect a bug, er, "feature", in the NVG510's firmware...


The Actual Setup

The fix, then, is to set everything up as described above - except... in the AEBS, I changed the last step:


- Under Internet, TCP/IP,

Configure IPv4: Manually

IP Address: <the RG's "Broadband IPv4 Address">

Subnet Mask: (Note that I'm not certain this is correct. The NVG510 doesn't show a subnet mask on its Broadband/Status tab, but the values I have showing would work with this mask.)

Router: <the RG's "Gateway IPv4 Address">

DNS: <the RG's "local" IP address (e.g., by default)>


Yay, It Works

No more lockups; everything is running smoothly with multiple devices accessing the Internet at the same time.


I'm going to mark this post as the answer, though hopefully I won't later get my hand slapped and told how I terribly messed things up - i.e., anybody trying anything I suggest in any post anywhere does so at their own risk, of course. I don't claim to be an expert - just yet another experimenter in the 'net world. Anybody with more expertise and good explanations is welcome to jump in!

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Message 14 of 90

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Re: NVG510 Bridge Mode???

"I did this set up using the actual setup steps.  It worked for me for about three weeks and now out of a sudden it stopped working."


Yes, Adricas19, I actually had the same thing happen. Mine's been going along smoothly - then suddenly wouldn't work anymore, seemingly out of the blue.


It turns out that AT&T turned on the IPv6 functionality in the NVG510. I don't know what about that broke the system, but to fix it, I simply went into the NVG510's setup and turned off the IPv6. Then, everything went fine.


On the Home Network tab, click the Configure link.

Change the IPv6 dropdown to Off.

Click the Save button.


If the NVG510 prompts you to restart the device, click the link there; otherwise, go to the Device page, click the Restart Device link, and follow the directions there (a few more clicks, and you'll actually restart the NVG510 Smiley Wink


The rest of your settings should stay the same as you had them from the solution earlier in this thread.


BTW, I spoke with an AT&T tech recently. He said that AT&T is now aware of at least a couple of problems with this modem (the DNS thing mentioned in this thread and an IP Diagnostics issue). They currently are planning to send out a firmware upgrade towards the end of this month (December 2011) to fix these issues. We'll see if that breaks anything else.... (not to be cynical or anything...)

Message 31 of 90

Re: NVG510 Bridge Mode???

Same problem here. 


I just got service 2 days ago, switching from comcast so this is a brandnew setup.  Internet works fine directly from the NVG510, but passthru not working to 3rd party router (I'm using a Netgear WNR2000)


Based on the information in this thread here's what I did in my setup to get it to work:

1. On the NVG510, I turned on IP Passthru, DHCPS-Fixed, using the MAC address of my Netgear router WAN port

2. On the Netgear router, I could see that it properly received the public IP address & gateway from the NVG510, but the subnet mask was set to  (I think this is wrong.) 

3. In order to change the subnet mask, I had to turn off the WAN port's DHCP client, and I manually changed the subnet mask to  I kept IP address and gateway as initially assigned by DHCP.

4. I also changed the DNS servers to use one from ATT,, but as a secondary I put in Google's Public DNS (


I also noticed that IPv6 is still turned on, and the Diagnostic test for IPv6 Continuity is failing.  In spite of that, my network is still working.  The OP seemed to require turning that off to get his to work, but mine is fine for right now. 


I also confirmed that this is a known bug with ATT techsupoort.  They told me that this is expected to be fixed in a patch due by the end of December (but at least 2 weeks out).  He told me it was priority #3, but he wouldn't tell me what the other top 2 were.  But I suspect alot of people have this very issue.


Message 32 of 90

Re: NVG510 Bridge Mode???

good job becuase there is no such thing as bridge mode in uverse

only version of it under uverse is ip passthrough.

Message 33 of 90

Re: NVG510 Bridge Mode???

lease in the nvg is no biggie i dont think it even works.

you are right with no leased static ip from att for an extra $15 a month

wan ip will change at a random point

Message 34 of 90

Re: NVG510 Bridge Mode???

this is normal. and it will change until you pay the extra to get static from att

Message 35 of 90

Re: NVG510 Bridge Mode???

uverse is not dsl there is no bridge mode

closest you will get is getting a 2nd router and using ip passthrough

Message 36 of 90

Re: NVG510 Bridge Mode???

@listfolks - woo hoo!  Thanks.  That whole IPv6 thing did the trick.  I'm back to using my router with the NVG510 acting as 'bridge' using the suggested set up here.


Now - here's a trick question.


I have a machine (virtual) running on my network in bridged mode (gets its own IP direct on the local network.)  I have this machine reporting my Broadband IP address to a dynamic dns service.  (


I also have my internal router (LinkSys E2000) forwarding port 80 to this same virtual machine.  I can access the web site running on my internal webserver (this virtual machine) NO PROBLEMS!  It's live to the world.


However this same web server has some SECURE site (HTTPS) applications running on it.  I can access those secure sites using the correct port when using the local IP address.  However - if I use either the Broadband IP address or the dynamic DNS domain name with the same port - the sites don't come up - browser says it's just a dead end.


I have port 443 forwarding to this same machine's IP address.


What could be going on here?



Message 37 of 90

Re: NVG510 Bridge Mode???

Hmm, thinking this through, drosengarden...


First, were your HTTPS sites ever working since you got the NVG510? (Trying to figure out where/when they actually stopped working...)


Next, the IP Passthrough should be allowing all traffic to go through to your Linksys E2000. Therefore, your port forwarding schemes (80 and 443) should, theoretically, work correctly.


So, the next thoughts that come to mind are certificates and MAC address. Your NVG510 has a different MAC address than the gateway you had previously. The VM has some virtual MAC address being assigned to it. Is that MAC address the same as it has always been? Is there anything in your setup that depends on either of these MAC addresses?


Is there anything in your certificate(s) that needs to be re-generated since you have a new configuration (new public IP address?, new MAC address?)


And, finally, exactly which HTTP error means "it's just a dead end"? Smiley Wink 404 - page not found, 500 - internal server error, ...???


I'm thinking this issue may deserve a thread of its own. You could start a new one and link to it here...

Message 38 of 90

Re: NVG510 Bridge Mode???

The posting by lisfolks above is simply excellent and works. A bit of clarification for those with limited experience....


 1) Many routers use as the router address so in the NVG510:

             instead set the DHCPv4 Start  Address to

             and set the DHCPv4 End  Address to  (...yes they are both set to

Be sure and set the range of IP addresses that your router/gateway DHCP server can assign to not greater than    ....OR....

 Just make sure that any IP addresses assigned by your router/gateway DHCP server are never used anywhere else.


2) The router/gateway that you connect to the NVG510 must be set for Manual or Fixed IP. The ATT Broadband IPv4 Address and Gateway IPv4 Address can be found on the NVG510 Status page. They must be set as the Fixed IP and Gateway addresses and yes...the subnet is correct.


3) Some routers will need to have the Primary DNS and Secondary DNS IP address manually set as well. These also can be found on the NVG510 Status page.

>>>An option is to instead use Google's public DNS servers. Their Primary DNS IP address is and their Secondary DNS IP address is


4) Be sure that IPV6 is set ot OFF on the NVG510 Home Network / Configure page.


Observations:  The basic ATT internet service is Dynamic IP which means that ATT can change your public IP address whenever they want to. With the above configuration your internet connection will be instantly dead if ATT changes your public IP address.

The fact that the NVG510 passthrough mode works as it does may be a legitimate bug but I suspect otherwise. It could be the sort of bug built into cell phone firmware intended to keep you you from activating a cell phone bought from one carrier with a different carrier. ATT sells Fixed IP addresses in minimum blocks of five addresses for an additional ~ $15 per month. Without this feature/bug in the NVG510... A Fixed IP is completely unnecessary unless you simply must have one.   It's a business decision....Follow the money!!!!


Message 39 of 90

Re: NVG510 Bridge Mode???

drosengarden wrote:

However this same web server has some SECURE site (HTTPS) applications running on it.  I can access those secure sites using the correct port when using the local IP address.  However - if I use either the Broadband IP address or the dynamic DNS domain name with the same port - the sites don't come up - browser says it's just a dead end.


I have port 443 forwarding to this same machine's IP address.

Are you sure your E2000 supports WAN IP address on your intranet?


I posted this same question elsewhere on this forum (no repsonse) but I think the NVG510 doesn't support local access of port forwarded servers using the WAN IP. A couple of years ago I was using a a Netgear VPN router with the ATT 2701 set in bridge mode just to get VPN remote access (no port forwarded then).


Then last year I switched out the ATT 2701 and used a BritePort 8201 modem configured in bridge mode connected to a Cisco RVS4000 VPN router to do what I think you're doing (Homeseer and HSTouch?). The RVS4000 allows local access to WAN addressed servers. This allows me to loop back test my HTTP webpages and use the same URL on my tablets when I'm inside my house or accessing my websites from internet hotspots.


Reading from this list, it doesn't look like I'll have a hands-off self repairing network (and yes, dynamic IP addresses change or they wouldn't call them dynamic) until we have a way for our third-party routers to work as they are designed. The NVG510 seems okay for the simple household (mine took 3 factory resets before it started behaving). 


<Vent alert> Gone are the days when a household family had one computer and one printer attached to the computer. Even my mother-in-law has a computer, laptop, tablet and a network printer. When I described my setup to ATT Tech support they commented that I sound like a business not a household. <Vent off> 


Message 40 of 90

Re: NVG510 Bridge Mode???

mccwam01 wrote:


"Reading from this list, it doesn't look like I'll have a hands-off self repairing network (and yes, dynamic IP addresses change or they wouldn't call them dynamic) ..."


A self-proclaimed AT&T employee responded earlier in this thread that the IP address won't change unless they swap you to a different port or change something up the line.


I agree this is against the idea of "dynamic" IP addresses, but think about it. AT&T is automatically turning on IPv6 on these devices. If they're going to start using IPv6, then everyone will have "static" IP addresses - that's a given with IPv6. When the IPv6 transition is complete, every device will have its own unique IP address. We'll no longer be using the 192.168 or 10.0 style IP (IPv4) addresses.


So, AT&T may be going away from dynamic IP addresses in their IP-DSL setup, since they're going to have to change their system anyway. Right now they have to keep the IPv4 addresses to tunnel the IPv6 through for devices/sites that can't use IPv6 yet. However, the IPv6 changes are moving along fairly quickly, so within the next couple of years, we may ALL have static IP addresses on each of our devices! (Now, how we'll be charged is an interesting question... by device and device type, perhaps? Say, every computer's access costs $x per month, each printer costs $y per month, and how much for those tablets and smartphones? Or, will our devices be registered to our account and they'll charge us strictly for bandwidth usage for all the devices on a given account, maybe?)


Message 41 of 90

Re: NVG510 Bridge Mode???

I guess many problems would disappear if a switch behind the NVG510 would be used instead of using another router behind that router, which is not a good idea at all. Below is my network layout where VPN is working fine, but MicroCell is not working.


Network Map

MicroCell is more important for me, so I switched to the second configuration, where IP Passthrough is turned OFF, MicroCell is connected to the modem directly and working fine, DIR-655 is connected to the modem. My computer was connected to DIR-655 and now is connected directly to the modem. VPN (PPTP) didn't work in both cases and I saw "GRE blocked" on the DIR-655, when my computer was connected to it.

Message 42 of 90

Re: NVG510 Bridge Mode???

I don't even see VPN requests from my home computer to the router at work (router's logs), which means the VPN stops on my modem at home, right? But when the modem is in Passthrough configuration - the VPN is working fine. This is weird.

Message 43 of 90

Re: NVG510 Bridge Mode???

OK, as I was told by AT&T tech, there is no PPTP passthrough in NVG510. Let's hope they fix it in the next firmware update.

Message 44 of 90

Re: NVG510 Bridge Mode???

I was able to get my setup working using pass-through on the NVG510. My Cisco router supports loopback so I don't have to change anything when I take my laptop outside my intranet. The router also forwards the right ports to each (different) servers.  The MicroCell seems to work (cellphone clarity is very good). The Netgear WPN824 was my router (some time ago) but I've repurposed it as an access point (only) now.


My laptop can also VPN back into my intranet using Cisco's QuickVPN Client software.


For clarity I chose not show all my network attached devices   








Message 45 of 90
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