How To: Nslookup (Mac OS X)
Mac OS X has a command-line utility for performing an nslookup called "nslookup". An nslookup is a network utility used to resolve a name (e.g. www.unh.edu) to an IP address (e.g. 126.96.36.199).
To perform an nslookup on a Mac OS X computer, you must open a Terminal window. Terminal can be found by opening the Finder, selection Applications and Utilities. To open a terminal session, double-click on "Terminal.app".
From the Terminal prompt, enter "nslookup www.unh.edu" to return the IP address for www.unh.edu. You may also do an nslookup for a non-UNH address such as Google. The nslookup results will display the actual IP address (or addresses) for the name queried. In addition the nslookup will also return the name server used to make the request. In this example, the name server is 10.20.248.13. This value will vary depending on your location and connection to the network.