Library /sys$common/syshlp/latcp$help.hlb CREATE, PORT, Parameter  *Conan The Librarian (sorry for the slow response - running on an old VAX)

 port-name

    Specifies the port name in the form LTAn:, where n is a unique
    number from 1 through 9999. If the port you specify already
    exists, LATCP returns the following error message:

    %LAT-W-CMDERROR, error reported by command executor
    -SYSTEM-F-DUPLNAM, duplicate name

    If you do not specify the port name, you must specify the
    /LOGICAL qualifier.

                                  NOTES

       When creating a port, note the following:

       o  Digital recommends that you assign a logical name when
          creating a port, instead of specifying a specific LTA
          device.

       o  You cannot use the CREATE PORT and SET PORT commands,
          along with the DCL command SET TERMINAL, to change the
          characteristics of a DECserver port unless there is an
          existing LAT connection to that DECserver.