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Contributor
schaasm1
Posts: 5
Registered: ‎09-10-2012
Accepted Solution

Dynamic DNS connection problems - DNS Server not responding

I was having frequent (several times a day) problems with DNS Server not responding. My IPV4 was configured to obtain a DNs server dynamically.  I did some searching on the internet, and found a recommendation to hard code DNS servers in my IPV4 configuration. The primary and alternate DNS servers that I used are from OpenDNS. They are 208.67.222.222 and 208.67.220.220, respectively.  Since I made that change 3 days ago, I have not had any problems with DNS server not responding.

 

Others with this problem might want to consider this solution.

Connection Expert
EG
Posts: 42,581
Registered: ‎12-24-2003

Re: Dynamic DNS connection problems - DNS Server not responding

Was this in a router's config or a computer O/S ?

Contributor
schaasm1
Posts: 5
Registered: ‎09-10-2012

Re: Dynamic DNS connection problems - DNS Server not responding

I'm running Windows7 through a wireless connection. To change the IPV4 configuration to hard code DNS servers I: navagated  Network and Sharing Center -> Change Adapter Setting -> Wireless Network Connection -> Properties -> Networking tab -> Internet Protocol Version4 -> Properties -> Use the Following DNS Server Address. Entered the 2 IP addresses.

 

Does this answer your question?

Connection Expert
EG
Posts: 42,581
Registered: ‎12-24-2003

Re: Dynamic DNS connection problems - DNS Server not responding

[ Edited ]

O/k. Some routers have difficulties performing *proxy / relay DNS* which many do by default. That said, FWIW, in this age of CDN's,  streaming video content, gaming, and other services, it is typically better to use the ISP's provided by default DNS servers. Even if their IP's need to be *hardcoded*.

Contributor
schaasm1
Posts: 5
Registered: ‎09-10-2012

Re: Dynamic DNS connection problems - DNS Server not responding

What are Comcast's DNS server IP addresses if you think I should use them rather than OpenDNS's?

Connection Expert
EG
Posts: 42,581
Registered: ‎12-24-2003

Re: Dynamic DNS connection problems - DNS Server not responding

[ Edited ]

Try hardcoding them in to the router's config if you can. 75.75.75.75 and 75.75.76.76

Contributor
schaasm1
Posts: 5
Registered: ‎09-10-2012

Re: Dynamic DNS connection problems - DNS Server not responding

Thank you for giving me the Comcast DNS server addresses. As I said before, I'm currently using OpenDNS as the DNS servers in my IPV4 configuration.  Before switching to the Comcast servers, I tried some ping tests.  Pinging of 75.75.75.75 for 10 reps with a 8192 message size and a 10-second timeout period, resulted in about 50% of the pings timing out.  Pinging the OpenDNS addresses resulted in no time outs.

 

The bottom line: I'm sticking with the OpenDNS servers 208.67.222.222 and 208.67.220.220. I have had no DNS failures since I hard coded these addresses over 1 week ago.

Thanks,

Steve

Connection Expert
EG
Posts: 42,581
Registered: ‎12-24-2003

Re: Dynamic DNS connection problems - DNS Server not responding

[ Edited ]

That's your choice of course but FWIW, pinging a Comcast DNS server is not a good measure of performance or an accurate troubleshooting tool as these servers are configured to de-prioritize / rate limit ICMP packet based ping probes / requests. This will cause them to show packet loss / slow response times when the are actually performing normally for real traffic / DNS requests.

Contributor
mfstanton
Posts: 6
Registered: ‎10-21-2012

Re: Dynamic DNS connection problems - DNS Server not responding

So what is the solution? I had some previous addresses from Comcast that worked fine until I reconfigured my router and it came up with  75.75.75.75 and its brother  75.75.76.76.  I am just not getting satisfactory performance and frequent timeouts just doing normal traffic to the Comcast.Net site. 

Contributor
schaasm1
Posts: 5
Registered: ‎09-10-2012

Re: Dynamic DNS connection problems - DNS Server not responding

Since my original posting on this thread on 9/10/12, I am using OpenDNS servers 208.67.222.222 and 208.67.220.220, and have had no DNS issues. You might want to give it a try.

Steve Schaaf - a Comcast Customer