IPv6 not working on RT-AC66R

[zaxcom]

I am using this router with a Arris SB6183 Modem. I am on TWC. The modem and the router are getting IPv6 setup information but every test I run for IPv6 connectivity fails.

What is wrong?

 

[jegesq]

How are you testing for IPv6 connectivity? I'm using the same setup (TWC, AC66U and native IPv6) and I never have trouble getting IPv6 connectivity.

There are two principal online sites for testing IPv6. One always gives me a score of 19 out of 20, and the other usually 18 out of 20.

You can always just do a really simple test like http://ipv6test.google.com/.

The other two key sites are: test-ipv6.com and ipv6-test.com.

Where are you located? I ask because sometimes TWC's servers in some of it's less populous areas have been known to have issues with IPv6. If that occurs, you should try changing your DNS server, and use something else like Google's DNS at 8.8.8.8 and 8.8.4.4 or Open DNS.

 

[zaxcom]

It fails on those sites. I get 0/10. Fails on every site I try.

I am using Google's IPv6 DNS servers; 2001:4860:4860::8888 and 2001:4860:4860::8844

I am in Charlotte NC.

 

[jegesq]

It fails on those sites. I get 0/10. Fails on every site I try.

I am using Google's IPv6 DNS servers; 2001:4860:4860::8888 and 2001:4860:4860::8844

I am in Charlotte NC.

Go into the GUI of your AC66R and on the WAN settings page, make sure you input the Google DNS servers using the IPv4 addresses for Google's DNS servers: 8.8.8.8 for primary and 8.8.4.4 for secondary.

Hit "apply" and reboot your router and then go to Google's IPv6 test page (link in message above).

What do you see? Should be an IPv6 address, no?

 

[zaxcom]

I already had those servers in my wan. It seems like the IPv6 address I am getting is not routable.

 

[jegesq]

And how do you conclude that the IPv6 address you are getting is not "routable?"

 

[zaxcom]

Not routable beyond my LAN. I am getting a private IP only, not one that is routable on the internet. All IPv6 tests fail on all sites.

 

[jegesq]

Yep. That's really odd and not consistent with my experience, which is that dual stack IPv4 snd Ipv6 (with 6 preferred) works fine. I'll post a screen shot later. Really odd.

 

[jegesq]

The GUI shows the settings for WAN; the test.jpg shows the results from IPv6-test.com which for some reason doesn't like IE11, and also dings me because TWC isn't providing a static IP linked to a specific hostname (obviously since I'm using Google's public DNS and because I'm not paying for a static IPv6 IP address either).

 

[PabloAbonia]

Jegesq, do you set Google DNS IPV6 addresses along with Google IPV6 addresses? Also, if I just use auto, TWC for me only gives out an Anycasted IPV4 DNS address and no IPV6 DNS address. Is that you experience as well?

I've never been able to get Native IPV6 to be stable with TWC, AC56U, Merlin 378.50.


--
Pablo

 

[jegesq]

Jegesq, do you set Google DNS IPV6 addresses along with Google IPV6 addresses?

No. You only need to set the IPv4 DNS servers and then on IPv6, you set it to "Native" and make sure DHCP-DP is "enabled". Also, for IPV6 DNS Settings, it should be set to "Connect to DNS Server automatically"-- Enabled.

Also, if I just use auto, TWC for me only gives out an Anycasted IPV4 DNS address and no IPV6 DNS address. Is that you experience as well?

No. That has not been my experience at all. Unless you have an ISP that is giving you a static IPv6 address, you're going to rely on "dual stack" which means that the DNS server assigned by IPv4 will also hand out, automatically, an IPv6 address, as long as you use "Native" and connect automatically to the DNS server.

I've never been able to get Native IPV6 to be stable with TWC, AC56U, Merlin 378.50.

.

I am not using an AC56, but I see no difference why it would be any different than the AC66. I've used almost every version of Merlin's FW, including 378.50, and haven't had any issues with IPv6.

 

[zaxcom]

I got it to work!!! This is the fix:

 

[neatchee]

I'm having the same problem on 378.51 but none of the solutions posted in this thread have worked. (DNS set as suggested, added IPv6 firewall rule, etc)

Any help troubleshooting this? I'm in Seattle on CondoInternet (local small ISP serving fiber to condos).

Thanks!

 

[jegesq]

I'm having the same problem on 378.51 but none of the solutions posted in this thread have worked. (DNS set as suggested, added IPv6 firewall rule, etc)

Any help troubleshooting this? I'm in Seattle on CondoInternet (local small ISP serving fiber to condos).

Thanks!

Which router? Which firmware? What kind of connection (PPOE, Automatic IP, PPTP, L2PT)?

First, got to the GUI page for "WAN -->Internet Connection" and find the settings for "Connect to DNS Automatically?". Make sure it's set to "No", and then type in Google's DNS in the blanks (8.8.8.8 and 8.8.4.4), and hit "Apply" on that page. Be sure not to forget to hit "apply" or else when you switch to the next page you will lose your changes-- you need to hit "apply" for every change.

Then go to the "LAN-->DHCP Server" settings page. DO NOT put anything at all in the "DNS Server" setting (leave it blank). If you have anything there, remove it and hit "apply" again.

Finally, go to the "IPv6" GUI page tab, and make sure that "Connection Type" is set to "Native" (since the Google DNS you entered above will support Native DNS). Before you hit "apply" here, make sure that "DHCP-PD" is set to "Enable". Then hit "Apply" after making these changes to the IPv6 page.

Then go to http://test-ipv6.com/ and you should be good to go with IPv6.

Works for me on both AC66U and AC3200 with my ISP, TimeWarnerCable. If you have trouble with Google's public DNS servers, try using OpenDNS or Level3's DNS. Better yet, try using your own ISP's DNS (just set "Connect to DNS Automatically" to "Yes", but do this only if you are sure your ISP is using and has fully provisioned IPv6.

 

[zaxcom]

Since I updated to 378.51 I no longer need to have the FE80::/10 forwarding rule. I have removed the rule and everything is working properly. I do use specified IPv6 DNS servers from Google though. I have entered:

2001:4860:4860::8888
2001:4860:4860::8844

as my IPv6 DNS and

8.8.8.8
8.8.4.4
as my IPv4 DNS

All DNS look ups now work as expected and IPv6 is preferred over IPv4 when available.