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Problem with DNS server 75.75.75.75?

SOLVED
Posted by
Visitor
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Member Since: ‎05-15-2013
Posts: 2
Message 1 of 7 (30,661 Views)

Problem with DNS server 75.75.75.75?

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

Member Since: ‎12-24-2003
Posts: 50,383
Message 3 of 7 (32,536 Views)

Re: Problem with DNS server 75.75.75.75?

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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Member Since: ‎10-28-2006
Posts: 470
Message 2 of 7 (30,622 Views)

Re: Problem with DNS server 75.75.75.75?

How is 75.75.76.76 reacting for you?

Posted by
Connection Expert

Member Since: ‎12-24-2003
Posts: 50,383
Message 3 of 7 (32,537 Views)

Re: Problem with DNS server 75.75.75.75?

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.

Posted by
Visitor
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Member Since: ‎05-15-2013
Posts: 2
Message 4 of 7 (30,566 Views)

Re: Problem with DNS server 75.75.75.75?

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
Edited on
‎05-15-2013 11:26 PM

Connection Expert

Member Since: ‎12-24-2003
Posts: 50,383
Message 5 of 7 (30,559 Views)

Re: Problem with DNS server 75.75.75.75?

[ Edited ]

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

Posted by
Visitor
Member Since: ‎07-27-2010
Posts: 7
Message 6 of 7 (29,294 Views)

Re: Problem with DNS server 75.75.75.75?

It is 8/13 and the same problem persists...
Posted by
Connection Expert

Member Since: ‎12-24-2003
Posts: 50,383
Message 7 of 7 (29,292 Views)

Re: Problem with DNS server 75.75.75.75?

Marked solved thread closed.