This is Part 3 of 4 in my series of posts on some of the simple utilities one can use to test networking and DNS configurations. This post will concentrate on using the utility dig to perform simple DNS server queries to ensure that your hostnames are resolving the way you expect them to.
Dig stands for domain information groper and is included in most Linux distributions nowadays (and probably most other Unix variants too). If you’re a windows user, you’ll have to download the dig program. One such site I’ve found for this program is http://pigtail.net/LRP/dig/
Much like nslookup, dig performs DNS lookups and displays the results from the queried name server. Most DNS administrators use dig to troubleshoot DNS problems because of its flexibility, ease of use and clarity of output. Dig tends to display its results in a format that DNS administrators recognize which resembles the setup for BIND. Other lookup tools tend to have less functionality than dig.
The most common things I use dig for are to: