Trying Out Different DNS Services

I recently ran across a problem with the DNS from my ISP. One of my clients moved their main website from one server to another and I waited for the DNS to propagate. And I waited and waited and waited some more. After four days, I was starting to get worried. Generally, the rule of thumb is that it takes a maximum of 48-72 hours for a domain name to become fully propagated across the various domain nameservers (DNS) on the internet. I contacted my ISP and they resolved the issue, but I was still bothered by the wait time and I know other people in the world must have experienced the same issue at one point or another. That’s when I decided to look into this whole DNS issue with my ISP. Let’s be honest – most people don’t care whether or not their using their ISP’s DNS or not. And probably 99.9% of the people out on the internet don’t even know what a domain nameserver is or does. I happen to be in that .1% that does know and care.

I work with a lot of websites and pointing domains from one server to another is a pretty common practice. I know from past experience that after pointing a domain to a new server, it’s often available within four or five hours. Because I’m in the website design and development business, getting an updated DNS is very important to minimize downtime when moving websites. So I started looking into the problem and the solution was much easier than I had anticipated – use a third party DNS! I started looking around and I found that there were two services out there that could really help me out. One was OpenDNS and the other was Google Public DNS. Both services are free, so I decided to try them out and compare them to my ISP.

The first service I tried was OpenDNS. I was a little confused when I first signed up for the OpenDNS Basic, but I quickly found that they offer a huge number of features that could be very useful. OpenDNS Basic has content filtering, phishing protection, botnet protection, stats, logs, shortcuts, and more. With all those features, I was impressed. With OpenDNS, you gain additional protection from problem websites, which is always a good thing. I think they’ve done an excellent job of creating a service that many people can really enjoy having – especially with that zero dollars price tag. The only problem I had is that I thought my computer was slightly slower when “looking up” websites. Perhaps it was just my imagination, but I’ll get to the DNS speed test results later.

My next test was with Google Public DNS. Google apparently launched the service in December 2009, but I hadn’t heard about it until I started looking into it. You don’t have to sign up for anything at Google, you just plug in your numbers and away you go. There are no fancy features like you’ll find with OpenDNS and that may appeal to some people. Again, Google Public DNS doesn’t cost anything, so that is always a pleasing feature. Beyond that, everything is no-frills. The Google DNS seemed to function without any problems, although it seemed to be a little slower than what I was used to.

I decided to test the speed differences between my ISP’s DNS, OpenDNS, and Google Public DNS using a program called namebench and another program called DNS Benchmark. Depending upon the time of day, configuration of the test, and the program used, my ISP generally beat OpenDNS and Google in response times.

Just from experience, I knew that my ISP was slighter faster than either of the other nameserver services. However, since my primary concern is with how often the DNS is updated, I needed to do a little more research. Each nameserver has its own update frequency specified by the person who installed the DNS and the Time to Live or TTL settings. While I don’t know the exact interval my ISP updates their nameservers, I do know from experience that it can sometimes take several days to resolve a proper domain. Again, since I frequently move websites from one server to another, I need quicker access.

OpenDNS seems to resolve their DNS’s rather frequently and they also have a neat tool called CacheCheck that can actually force them to update their DNS before the TTL expires. That is a really neat feature! I couldn’t find any information on how often Google updates their cache, but I’ve seen reports on the internet that they take slightly longer than OpenDNS. From what I can tell, OpenDNS and Google Public DNS refresh their caches far more frequently than my ISP.

So what am I to do? My ISP is definitely faster, and many other testers have discovered the same results. However, I need a DNS that resolves a recently moved website more quickly than my current ISP. Based upon my own DNS performance tests and the features benefits, I’m going with OpenDNS. If I decide later that I don’t like the service, then I always have the option of switching back to my ISP or choosing Google instead. Right now, I think I’ve made the right decision.