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

    If you want to use another name server as your default server,
    use the server command.

    $ nslookup
    Default Server:  condor.klg.dec.com
    Address:  16.99.208.53

    > server ns01.koz.dec.com
    Default Server:  ns01.koz.dec.com
    Address:  16.99.9.20

    If for some reason the default server is not responding, you can
    always use the lserver command to change the default server. The
    lserver command uses the initial default name server to lookup
    the IP address of the new server.

    > lserver collie.klg.dec.com
    Default Server:  collie.klg.dec.com
    Address:  16.99.208.10

    Or, if you already know the IP address of the new server, you can
    use the server command to reset the default server.

    >server 16.99.208.10

    > server 16.99.99.226
    Default Server:  beagel.zok.dec.com
    Address:  16.99.99.226