AT&T Internet 1000 not working with


I have AT&T fiber in the Alpharetta, GA area. Since first hearing about Cloudflare DNS on Security Now, I’ve attempted to use it. I found - confirmed using GRC’s DNS Benchmark connected directly to MY AT&T modem/router - that will not respond. However, the backup, does respond.

I contacted AT&T and went through several levels. It ended up with my a “higher tier” support person had me go to some websites and providing information to them - I did a restore from a backup on my PC after the call. They stated they’d send this up and it would be resolved in a few hours; followed by a few days. I had to leave town for work and forgot about it.

Today I decided to benchmark my DNS again. I found the same condition exists. I was wondering if anyone else has had this issue and found a resolution. Or if Cloudflare has a contact with AT&T to notify them that they are blocking access to a legitimate DNS server.

Some AT&T hardware improperly uses Just use the If you want a backup DNS choice, use (Google) or (Quad9).

More info is here:

What is your modem/router model (the ATT provided one)? There is a known issue with a couple of models that ATT is supposedly working on where the modem hijacks both CFDNS IPs. You can reach CFDNS via IPv6.

1 Like

As of 11/2/2018 - the transcript of my chat with AT&T Support. I also have the Fiber 1000 plan.

AT&T : Welcome to AT&T Social Media Chat. Are you available to begin chatting?
Me : yes
Taylor B : Hi Jared! My name is Taylor B. I’m happy to help.
Me : I’m not Jared
Taylor B : Can you explain whats going on?
Me : I’m trying to use Cloudflare’s DNS as my DNS provider
Me : But it seems AT&T is blocking those ip’s
Me : and
Taylor B : Okay no problem give me one moment
Me : i found a thread on Reddit that states: AT&T released firmware 1.6.7 (ARRIS BGW210-700 on AT&T Fiber) which fixed access to Cloudflare DNS for me.
Me : i guess i need to know if that’s the same fiber modem i have, and if i am updated to that revision
Taylor B : It looks like we have blocked Cloudflare and we are working to fix the issue
Me : ok - thanks for the info. any idea on when it’ll be resolved?
Taylor B : and its an issue with your residential gateway
Taylor B : Not at the moment
Taylor B : I apologize for the inconvenience
Me : ok - thanks for the info. i guess i’ll check occasionally for it being accessible.

My AT&T modem/router model is listed as 5268AC. Hardware version 260-2173300, software version as of today.

5268AC - 260-2173300
No access to yet. I use and instead.

One note about them saying that the issue is your gateway…
I ran a traceroute and it clearly shows that AT&T is passing off to a company called GTT Communications, Inc. (GTT), and then GTT is blocking on the GTT owned Cloudflare uplink router. At least it does for me:

8 ( 5.222 ms 4.271 ms 4.225 ms
9 * *^C
Please check your traceroute and see where it stops.

I had this problem. Then I had a problem with the modem/router and AT&T replaced it with a different brand, BGW210-700. Now works along with other DND IP addresses.