DNS change?

Tutor

DNS change?

 

Ive been using Uverse moderately successfully for quite a while, with an Apple time capsule wired to my AT&T-provided 3800HGV-B router/modem. All our devices normally connect to the APple wireless network for various reasons.

 

Yesterday all devices started to fail to reach the internet. A bit of poking around and testing determined that the reason the devices could not connect was that DNS was failing. (All machines were using default DNS setup, which as I understand it means that they receive their DNS server IPs through the AT&T gateway.

 

I can work around this two ways:

1) connecting to the wireless network the 3800HGV-B provides works fine with the default setup, ie AT&T's DNS servers.

2) connecting to the apple wireless network but explicitly configuring google DNS (8.8.8.8 and 8.8.4.4) works fine.

 

But I'm mystified why the AT&T DNS servers would suddenly stop working "indirectly" via the apple wireless network. Anyone know what may have changed on AT&T's side, and whether it can be switched back?

 

I do use double-NATing for the two network layers (the AT&T device shares out on 192.68.x.x, and the Apple device connects to that and shares out it's wireless on 10.0.1.x). I havn't tested what would happen if I switched the Apple device to avoid re-NATing, but as I said it has been working for quite a while this way.

 

-- Glenn

 

549 Views
Message 1 of 8
ACE - Expert

Re: DNS change?

Yesterday afternoon from before 12:30 PM ET to after 3:00 PM (these are times when we noticed it broke and when it seemed to be fixed), Network Solutions, which provides DNS services for millions of websites, had an issue with its DNS serving.  This may have been your problem because AT&T could not get authoritative DNS responses for addresses serviced by NS.

 

http://www.informationweek.com/internet/ebusiness/network-solutions-outage-third-time-not/240163027

 

http://www.pcworld.com/article/2056920/network-solutions-reports-more-dns-problems.html

 

*The views and opinions expressed on this forum are purely my own. Any product claim, statistic, quote, or other representation about a product or service should be verified with the manufacturer, provider, or party.
Message 2 of 8
Tutor

Re: DNS change?

Interesting, but I wasn't using my network during this time. All my issues have been since then (my network was fine @ 11AM eastern yesterday, no longer fine when I returned home approx 9pm eastern yesterday). Unless the Network Solutions outage left AT&T equipment outside my home in an unworking state, that shouldn't be the cause.
Message 3 of 8
ACE - Expert

Re: DNS change?

Unless the AT&T DNS caches had not gotten repopulated by then (doubtful).

 

Hmmm.....

 

 

*The views and opinions expressed on this forum are purely my own. Any product claim, statistic, quote, or other representation about a product or service should be verified with the manufacturer, provider, or party.
Message 4 of 8
Highlighted
Employee

Re: DNS change?

Hello onegee,

I recommend to restart your gateway to re-establish all connections. If this does not resolve your trouble I can help investigte the issue further. I have sent you a private message to ensure your services are restored.

SadathCS
ATTU-verseCare

If you encounter any issues with your service or equipment, I recommend checking out our Troubleshoot & Resolve solutions to help diagnose the issue.
Employee Contributor*
*I am an AT&T employee and the postings on this site are my own and don't necessarily represent AT&T's position, strategies or opinions.
Message 5 of 8
ACE - Expert

Re: DNS change?


JefferMC wrote:

Unless the AT&T DNS caches had not gotten repopulated by then (doubtful).

 

Hmmm.....

 

 


Actually, negative results can get cached and persist for a while.  Depends on TTL's, expirations, etc.

 

*The views and opinions expressed on this forum are purely my own. Any product claim, statistic, quote, or other representation about a product or service should be verified with the manufacturer, provider, or party.
Message 6 of 8
Tutor

Re: DNS change?

 

Just to close off the thread: oops, sorry, this was user error on my part.

 

At some point in the distant past I had inserted sonic.net DNS server IPs into my time capsule configuration. These DNS servers are what apparently stopped working the day before yesterday; AT&T's stuff was fine.

 

While it was a bit trickier in MacOS than in some other OSes to determine what DNS servers were actually being hit, I should have been able to find these DNS setting before bothering folks here; apologies again.

 

-- Glenn

Message 7 of 8
Employee

Re: DNS change?

Excellent! We are glad to know your issue was resolved. We are here to help and no worries, it is never a bother to post an issue you are having. Smiley Happy

 

SadathCS

ATTU-verseCare

If you encounter any issues with your service or equipment, I recommend checking out our Troubleshoot & Resolve solutions to help diagnose the issue.
Employee Contributor*
*I am an AT&T employee and the postings on this site are my own and don't necessarily represent AT&T's position, strategies or opinions.
Message 8 of 8
You must type a description before you click preview or reply.
Share this topic
Announcements

Welcome to the AT&T TV Hub!
We have some helpful articles located under TV Hot Topics.
On the left you will see DIRECTV and U-verse TV links. Click on those links for more information regarding Apps, Billing, and TV troubleshooting tips.

Additional Support