VMS Help AUTOGEN, MODPARAMS.DAT  *Conan The Librarian (sorry for the slow response - running on an old VAX)

    AUTOGEN reads a parameter file named SYS$SYSTEM:MODPARAMS.DAT
    during the GETDATA phase. You can add commands to this file to
    control the system parameter values and file sizes that AUTOGEN
    sets.

    The commands you add to MODPARAMS.DAT use the following formats
    to define symbols that control parameter values:

                                Symbol
    Operation                   Format         Example

    Increment a value           ADD_*          ADD_GBLPAGES=500
    Specify a minimum value     MIN_*          MIN_PAGEDYN=400000
    Specify a maximum value     MAX_*          MAX_PAGEDYN=400000
    Specify an absolute value   Parameter      SCSNODE="BIGVAX"
                                name

                                   NOTE

       Specify an absolute value only for parameters that AUTOGEN
       does not calculate, for example, SCSNODE and SCSSYSTEMID.

    For more detailed information, refer to the chapter about
    managing system parameters in the OpenVMS System Manager's
    Manual.