I recently got ATT U-verse service and I rapidly notice it started giving me all sorts of issues, like blank screen, slow loading, etc. So I started checking for possible issues ping was ok, there were not packet loss, it turns out the issue is forced ATT DNS timing out, causing all the trouble.

I said ok let me switch to Google DNS… It turns out ATT disabled the option to put custom DNS. Then I tought ok I got a Asus RT-AC66U let me put the NVG589 as bridge mode and the RT-AC66U takes care of the rest.

Tried google how to turn the the NVG589 into pure bridge mode, and found something that look promising a way to gain Root Access to the router to enable true bridge mode, but it turns out my brand new modem has an updated firmware with the exploit fixed. After some more googling I found that ATT uses 802.1x to authenticate their devices, so I cant give all the responsibilities to the RT-AC66U, I must used their DMZ+ ( Pseudo ‘Bridge mode’ ).

I found a great tutorial on the ATT forums to put my NVG589 into pseudo ‘bridge mode’ but when I did at first I lost IPv6 on my network. After some more reading it seems ATT enabled IPv6 in most places using a 6rd tunnel, my RT-AC66U has support for that type of tunnel, so I googled around what settings ATT used disabled IPv6 support on the NVG589 ( It basically turns off the tunnel. ) and applied the settings to my RT-AC66U and Boom, my RT-AC66U got both IPv4 and IPv6 public Ip Addresses and my whole network was able to browse the internet via IPv4 + IPv6.

Now my internet is blazing fast, I get no hang pages, or slow loading on youtube because of timed-out dns queries.  One thing still holds true since this is a psudo bridge mode, the NVG589 still does the NAT for IPv4 and its limited to 2560 but this only applies to IPv4 as IPv6 is via a tunnel and does not count.

Disclaimer: I am not responsible for any damage to your device(s) or anything that goes wrong. Proceed at your own risk.

Before we start

Make sure you have a laptop or a computer that you can connect directly into the NVG589. Unplug all ethernet cables from the NVG589 except for the one going into the aforementioned laptop. Write down the MAC address of your personal router (the WAN MAC address if you see different ones for LAN and WAN)

Settings on the NVG589

  • Login to your NVG589 by going to
  • Go to ‘Home Network’ then ‘Subnets & DHCP’.  Your password is on the side of the modem.
  • If your ‘Device IPv4 Address’ is the same subnet as your local router, I suggest changing it.
    • I changed mine to but you can stick with whatever you like / need.
    • And changed my subnet mask to ( Limit valid Ip Addresss to only 6 )
    • Change ‘DHCPv4 Start Address’ to (or whatever your above Device IPv4 address is but with a 1 at the end instead of .254)
    • Change ‘DHCPv4 End Address’ to,  We need these for any IPTV STB, but It’s important that you only have the laptop plugged into the ethernet at this point.
  • Click  -> ‘SAVE’ at the bottom.
  • Go to ‘Home Network’
    • Got to ‘Wireless’
      • Turn wireless off.
    • Go to ‘Configure’
      • Turn IPv6 off.
  • Go to ‘Firewall’ then ‘ ‘Packet Filter’. Click -> ‘Disable Packet Filters’  ( Again, we want our router to do the work. ) Make sure you don’t have any of your own settings turned on in ‘NAT/Gaming’ (don’t worry if you see 1 in there already that you can’t delete).
  • Go to ‘Firewall’ then ‘IP Passthrough’.
    • For ‘Allocation Mode’ select ‘Passthrough’
    • For ‘Passthrough Mode’, select ‘DHCPS-Fixed’
    • Type in the MAC address for your router under ‘Manual Entry’, lowercase is fine.
  • Click -> ‘SAVE’  **  It will tell you that it needs to reboot.  Hang on for a minute. **
  • Go to ‘Firewall Advanced’ at the top and turn everything OFF.
  • Near the top of your screen, you should see an option telling you to reboot the router. Go ahead and do this now. It takes about 2 minutes.
  • While the NVG589 reboots unplug your laptop from it, and connect your RT-AC66U and the IPTV STB to the back of the NVG589.

Settings on my RT-AC66U

Note: You can use other routers. But this instructions are aimed for RT-AC66U.

Login to your RT-AC66U.

  • Go to ‘WAN’
    • Change ‘WAN Connection Type’ to ‘Automatic IP’.  ( This will give your personal router the external IP of the NVG589 )
    • ‘Enable WAN’,
    • ‘Enable NAT’ and ‘Enable UPnP’ is all set to YES for me.
    • I recommend Setting your own DNS server ( This is the main point of the tutorial replacing the ATT DNS with something better. )
    • I use Google’s but you use whatever you like.  Google’s is and
    • ‘Account Setting - Authentication’ is ‘None’.
    • There are no Special requirements from ISP at the bottom.
    • Hit ‘APPLY’ at the bottom and your router will reboot.
  • After the reboot your RT-AC66U should have a public IP Address and access to the internet but still missing IPv6.
  • Go to ‘IPv6’
    • Conection type ‘6rd’
    • DHCP option ‘Disabled’
    • IPv6 Prefix ‘ 2602:300:: ‘
    • IPv6 Prefix Length ‘28’
    • IPv4 Border Router ‘’
    • For DNS use I use Google’s but you use whatever you like.
      • Google’s is 2001:4860:4860::8888 and 2001:4860:4860::8844
    • Hit ‘APPLY’ at the bottom and your router will reboot.

Thats it after this if everything went correctly you should have both IPv4 + IPv6 on your RT-AC66U with custom DNS.

This tutorial is the merged of two post that I found on the internet :