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Problem with DNS server 75.75.75.75?

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Message 1 of 7
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If I do a ping to 75.75.75.75, I get timeout errors.  But if I ping OpenDNS or the Level3 DNS servers, all is OK.  I liked the Comcast DNS server because it is faster when it works but the timeout errors will cause my browsing to slow-down.  What is going on with the 75.75.75.75 DNS server?

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Posted by
Connection Expert

Message 3 of 7
45,340 Views
Solution

FWIW, the default Comcast DNS servers are deliberately configured to de-prioritize / rate limit ICMP packet based ping probes, so pinging them is not a good method to use to gauge their performance.




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6 REPLIES
Posted by
Problem Solver

Message 2 of 7
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How is 75.75.76.76 reacting for you?

Posted by
Connection Expert

Message 3 of 7
45,341 Views
Solution

FWIW, the default Comcast DNS servers are deliberately configured to de-prioritize / rate limit ICMP packet based ping probes, so pinging them is not a good method to use to gauge their performance.




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Posted by
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Message 4 of 7
41,595 Views

For me, 75.75.76.76 was doing the same behavior as all-75's.

 

So, if ping is not a good measure, what is?

 

BTW, when I first setup my router maybe 1 yr ago, I did the same tests, and the 75's was consistantly the fastest, with no timeouts.

Posted by
Connection Expert

Message 5 of 7
41,588 Views

DNS benchmark tools such as these that measure actual resolution times are;

 

http://code.google.com/p/namebench/

https://www.grc.com/dns/benchmark.htm




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Posted by
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Message 6 of 7
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It is 8/13 and the same problem persists...
Posted by
Connection Expert

Message 7 of 7
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Marked solved thread closed.




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