I’m currently in the process of moving our DNS over to another provider and I was curious as to whether the old or new provider offers faster lookups. dig
shows query times, but I didn’t want to just run that over and over. I decided to write something to do this, in Java since I like Java. I found this post, which has the meat of the work done already. I also read some of Sun’s JNDI/DNS lookup info, which was pretty dense. All I want to do is specify the name server’s IP and do the lookup. I don’t even really care about the result, just how long the query takes.
The thing I wrote only looks up A
records, but can easily be modified to do CNAMEs or whatever. Here’s how you call it:
$ java -jar DNSTester.jar 4.2.2.2 www.google.com 25 Resolved www.google.com to 74.125.235.19 against NS 4.2.2.2 Performed 25 lookups in 233.29 milliseconds. Average 9.3316ms per lookup. $ java -jar DNSTester.jar 8.8.4.4 www.google.com 25 Resolved www.google.com to 74.125.226.146 against NS 8.8.4.4 Performed 25 lookups in 450.034 milliseconds. Average 18.00136ms per lookup.