4.2.2.2: The Story Behind a DNS Legend

Previous discussion: <a href="https://news.ycombinator.com/item?id=1282213" rel="nofollow">https:&#x2F;&#x2F;news.ycombinator.com&#x2F;item?id=1282213</a> (94 points, 1250 days ago, 39 comments)

I noticed very strange but consistent performance behavior from Google Public DNS. Even though a DNS record was cached, the response time was in the range of 20-30ms, which is absolutely horrible. When I switched over to OpenDNS, cached response times dived down to 1ms. Needless to say just made the switch on all the servers to OpenDNS. Can anybody explain this behavior?<p>Here is the GitHub gist showing the output:<p><a href="https://gist.github.com/nodesocket/786e3b879f74c7787ca6" rel="nofollow">https:&#x2F;&#x2F;gist.github.com&#x2F;nodesocket&#x2F;786e3b879f74c7787ca6</a>

There are different reasons to use the various dns servers:<p>Both Google (8.8.8.8 &#x2F; 8.8.4.4) and OpenDNS (208.67.220.220 &#x2F; 208.67.222.222) can be troublesome on small networks when trying to reach local LAN devices because they resolve failures to their own search pages. My fallback here is to always try one of the L3 servers (4.2.2.1 - .6)<p>OpenDNS is my goto when I need filtering. OpenDNS is also great when changing ip addresses on domains because you can clear their public cache and make sure everything is updated and is working immediately. <a href="http://www.opendns.com/support/cache/" rel="nofollow">http:&#x2F;&#x2F;www.opendns.com&#x2F;support&#x2F;cache&#x2F;</a><p>Google DNS tends to make youtube streaming work much better for me.<p>Even Comcast has even recently changed their dns to memorable numbers 75.75.75.75 &#x2F; 75.75.76.76

I&#x27;ve been using 4.2.2.2 on almost daily basis since 2003 - every time I want to see if I&#x27;m connected to the Internet, anywhere in the world - that&#x27;s my canary.<p>It had never occurred to me to wonder <i>why</i> I was using 4.2.2.2. Just something I learned from one our network engineers, who learned it from someone else...

I started using 4.2.2.1 in early 1999. A friend of mine was a sysadmin at Genuity (then the new owners of that block) and they used it a lot internally. I went on to show it to a lot of my fellow sysadmins and I guess a lot of other folks did the same.

I did not understand why we shouldn&#x27;t use 4.2.2.2. If they did not wan people to use it, why is it open? Too bad none of the reports the authors has read about that were linked.

Just imagine how much traffic they get.<p>If they really didn&#x27;t want people to use it, I am sure it would be easy for them to block whole swaths of the net from using it.

Why 18.62.0.96 in particular for testing web service? Does MIT provide that IP as a public service?

Been using 4.2.2.2 (and 4.2.2.3) for almost a decade now.<p>In recent years I stopped using them though because of privacy and reliablility causes; I usually setup a caching server on the local host or network.

Google should be tracking all the queries on their DNS server.

Is there a tool for automatically benchmarking various public DNS servers (along with your ISP&#x27;s) to determine the best choice?

I&#x27;ve been blocked by 4.2.2.2 before for (I assume) over-use. It took a year or two but they eventually noticed my traffic..

I am curious if google is using the data from its dns service to improve the search index.

I use 8.8.8.8 which is Google&#x27;s public DNS