VMS Help BACKUP Command, Qualifiers, /LOG  *Conan The Librarian (sorry for the slow response - running on an old VAX)

       /LOG
       /NOLOG (default)

    Command Qualifier

    Determines whether the file specification of each file processed
    is displayed on SYS$OUTPUT during the operation. The default is
    /NOLOG. Displays at your terminal the file specification of each
    file processed during the BACKUP operation (/LOG) or suppresses
    the display (/NOLOG). The default is /NOLOG.

    Do not use /LOG together with /LIST when the output for /LIST is
    directed to the terminal; you will receive confusing output.