VMS Help LANCP, TRIGGER, NODE, Qualifiers, /DEVICE  *Conan The Librarian (sorry for the slow response - running on an old VAX)

       /DEVICE=device-name

    Specifies the LAN controller device name to be used for sending
    the trigger boot messages. For example, you can specify a DEMNA
    controller as EXA, EXA0 or EXA0:.