Not applicable

Spectrum IPv6 DNS Issue

As of Wednesday 6/6, I am now getting IPv6 DNS servers sent down to my Spectrum modem which are superceding the regular IPv4 DNS servers I have setup in my router.  I have Google's 8.8.8.8 & 8.8.4.4 DNS servers configured as static DNS servers in my router's config, but when I look at the status page of my router, there are 2 Spectrum DNS servers in addition to my 2 Google DNS entries.  The Spectrum DNS servers are 2001:1998:f00:1::1 & 2001:1998:f00:2::1.  These DNS servers aren't working right, and are causing my Amazon fire sticks to not load some apps, take a long time to load apps, take a long time to load thumbnails, etc.  I've confirmed these servers are problematic by using nslookup from my laptop and get nothing but failures when attempting to use these DNS servers.  When I disable IPv6 on my laptop and use Google's DNS, nslookup works fine.  I cannot disable IPv6 on the fire sticks, and I cannot disable IPv6 from my Netgear C6250 router.  I need these bad IPv6 DNS servers out of my network, but don't see any way to accomplish this. 

 

Anyone else seeing an issue like this?

5 REPLIES
Not applicable

Re: Spectrum IPv6 DNS Issue

I wonder if this is happening to me too. I don't know anything about the back end routers, but within the last week certain apps on my Galaxy S5 load very slowly. But oddly, my other WiFi devices work just fine. Maybe some sort of update broke something?
Established Sharer

Re: Spectrum IPv6 DNS Issue

@fiberwireand @tykerr -

If you want to use both IPv6 and traditional IPv4, you should be using the Spectrum DNS server IP addresses 209.18.47.61 and 62.  They are automatically offered to your router from the modem when the router boots up if your router is set to get settings from the WAN port. If you load an external DNS Spectrum cannot guarantee that it will work properly with the dual-stack modem configuration that Spectrum requires.  Indeed, @fiberwire seems to have the problem resolving IPv6 and @tykerr does not.

The following information is in the IPv6 FAQs which are pinned at the top of this specific sub-forum: 

What DNS resolvers should I use with IPv6?


We provide DNS resolvers in configuration information automatically provided via the Dynamic Host Configuration Protocol (DHCP and DHCPv6). At this time, we are only providing the IPv4 addresses of our DNS resolvers. We expect to add IPv6 resolvers in the coming months.

As long as IPv4 is working, your dual-stack (IPv4 and IPv6 simultaneously) configuration will still allow you to use IPv4-enabled DNS resolvers to look up IPv6 addresses.

 

Valued Contributor

Re: Spectrum IPv6 DNS Issue

May be able to "force" the router to use manually set DNS if the auto option is indeed linking you to v6 lookups. Methods can vary across brands, but you may see an option in the WAN section that mentions automatically connecting to DNS. Toggling that off should allow you to set specific entries.

Should also note you would also need to designate for the router to resolve DNS lookups not done at the client.

That is another possibility... could manually configure devices to do their own lookups directly to specific servers in their network configs. Make sure to bind their addresses in DHCP though if you go that static address route to avoid future conflicts.
Not applicable

Re: Spectrum IPv6 DNS Issue

I do not want to use IPv6 in any capacity, however my router does not give me the option to disable it, so I'm forced to live with it.  When I set my router to get DNS via DHCP, then I get the following DNS servers, in order:

2001:1998:f00:1::1
2001:1998:f00:2::1
209.18.47.61
209.18.47.62
209.18.47.63

 

The top 2 IPv6 DNS servers do not respond to nslookups:

nslookup microsoft.com
DNS request timed out.
timeout was 2 seconds.
Server: UnKnown
Address: 2001:1998:f00:1::1

DNS request timed out.
timeout was 2 seconds.

 

Running the same nslookup with 8.8.8.8 as DNS server responds correctly.

 

The verbage you referenced saying Spectrum does not offer IPv6 DNS must be outdated.  I'm getting IPv6 DNS servers sent to me from Spectrum.  When I do a whois lookup on the IP's, it comes back with Spectrum/Time Warner as the owner.  A Google search of these IP's also brings up references that other people are getting these as well and causing problems. 

 

Not applicable

Re: Spectrum IPv6 DNS Issue

I do not see an option like this in my router.  I can either have DNS servers populated via DHCP, or set them manually.  That's it.

 

For your last point about setting static addresses.. this works but only if the device does not support IPv6.  If the device does support IPv6, it does not matter what I set for static IPv4 DNS servers, they are always superceded by these IPv6 servers:

2001:1998:f00:1::1

2001:1998:f00:2::1