dig—Send domain name query packets to name servers
dig [@server] domain [<query-type>][<query-class>][+<query-option>][–<dig-option>][%comment]
dig (domain information groper) is a flexible command-line tool that can be used to gather information from the Domain Name System servers. dig has two modes: simple interactive mode that makes a single query, and batch that executes a query for each in a list of several query lines. All query options are accessible from the command line.