AT&T Internet 1000 not working with 1.1.1.1


#1

Hi,

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 1.1.1.1 will not respond. However, the backup, 1.0.0.1 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.
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#2

Some AT&T hardware improperly uses 1.1.1.1. Just use the 1.0.0.1. If you want a backup DNS choice, use 8.8.8.8 (Google) or 9.9.9.9 (Quad9).

More info is here:


#3

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.