VMS Help TCPIP Services, NSLOOKUP, Default Options  *Conan The Librarian (sorry for the slow response - running on an old VAX)

    NSLOOKUP has options which influence the type of information you
    receive from a query and the way NSLOOKUP behaves. Some of the
    options take a value and others are boolean options. The options
    have default values and can be changed by using the set command.

    You obtain a list of the options and their default values by
    entering the set all command immediately after starting an
    interactive NSLOOKUP session.