Here is a great link about all those DNS questions in plain English!
Here are a couple of quick snippets of the more frequently used NS commands to help troubleshoot those dreaded DNS issues.
Get the authoritative server names and IP addresses for your domain:
(replace “belchamber.us” with your domain of course)
In your server shell at the command line, type this command to get your NS information
host -t ns belchamber.us
To troubleshoot DNS issues and get get your In Windows, go to Start, then type “cmd”, then at the prompt, type:nslookup -q=mx belchamber.us