Library /sys$common/syshlp/tcpip$ucp_help.hlb SET, HOST, Parameters  *Conan The Librarian (sorry for the slow response - running on an old VAX)

 host

    Required.

    Name of a host that is a source or destination of internet
    communications.

                                   NOTE

       To define a name in lowercase or mixedcase, enclose it in
       quotation marks.

       If you define a mixed-case name, also define an alias in
       either all uppercase or all lowercase characters.

       You cannot delete a host by specifying its alias.