Unreliable DNS servers - replace them

[Tortanick]

Is your ISP's DNS servers unreliable? there are quite a few public DNS servers around the ol' net, I havn't tested any of these but some of them should work.

4.2.2.1
4.2.2.2
195.20.105.149
213.133.115.5

These lot are from the Democratic DNS system: OpenNIC, sadly their plans to replace ICANN are on hietias, but most of the DNS servers should work.

(Cologne, DE) - 217.115.138.24
(Tokyo, JP) - 219.127.89.34
(Tokyo, JP) - 219.127.89.37
(Auckland, NZ) - 202.89.131.4
(London, UK) - 194.164.6.112
(Phoenix, AZ, US) - 63.226.12.96
(San Francisco, CA, US) - 64.151.103.120
(Longmont, CO, US) - 216.87.84.209
(Los Angeles, CA, US) - 67.102.133.222
(Luik, Belgium) - 83.217.93.246

And these are from the open root server confediration

199.166.28.10 - Atlanta, Ga
199.166.29.3 - Nederlands
199.166.31.3 - Orlando, FL, USA
204.57.55.100 - Boston, MA, USA
199.5.157.128 - Detroit, MI, USA

And finally cesidian root
66 . 92 . 233 . 14
24 . 129 . 114 . 64
217 . 57 . 37 . 202

TODO: test, If anyone has an easy wat to test these please post.
how to tell if the DNS servers are at fault, and how to replace them

[dbarrow]

4.2.2.1
4.2.2.2
The Verizon servers can be very handy when Comcrap servers have a snit.

Comcast has had an up and down battle with this for years. There are times when page resolution hangs for excessive periods, enough to yield a page not found error.
Ping plots to the URL often show no lags that should be the cause, or, a ping plot to the Comcast DNS servers will show a severe lag.

In many cases, switching to the Verizon DNS servers will show immediate improvement.

The problem can be persistant for several days following any major outage or large scale internet disruption as it takes several days for the DNS servers to "re-populate" completely whenever they go off line. In those cases, the Comcast DNS server has to "reach out" to the major ICANN backbone DNS servers to resolve the address and does not store it until called and searched for.

Whenever I encounter this problem, which seems more and more frequent, I change to the Verizon DNS servers to see which is faster.

Testing is more experimentation than anything else.
Keep the DNS server address in Ping Plotter and run a quick ping trace to look for lag. Determine if this is slow response from the server (end hop) or somewhere in the system prior to it.
(I am showing a heavy lag today on the first hop to the primary server for my node, which a Comcast guy told me a week ago they have been having problems with, so it is therefore not the DNS server but the first sub-station on the route to the server.)

Change the DNS server.
Go into your router menu\ configuration and find the box for DNS. Usual default is checked "obtain automatically from ISP"
Change to "static" address and enter an alternate DNS server. Save and exit.
Run Ping Plotter against that address and compare for any differences again, looking for lags in the hops preceeding it to rule out a slow spot within the ISP network. If you see the same lags within the system as with your ISP DNS servers, the problem lies somwhere between you and the gateway to the DNS server.

Note: since the NYC power outages, the ATT backbones above Comcast level have been very laggy for over a week with some major speed bumps.
Remember that this is an ATT problem and Comcast can't do anything about it except complain.

[Tortanick]

Thanks for the help dbarrow, just one question: what is ping plotter and how do you use it?

[dbarrow]

www.pingplotter.com

Enter the IP or URL and trace all the hops from your machine to the target. Shows response time on each hop.
Info on use on the site.

[Tortanick]

thank you.