The RMU Monitor Stop command stops the Oracle Rdb monitor process
    (RDMS_MONITORnn, where nn represents the version Oracle Rdb)
    normally, either with a shutdown and rollback of the databases or
    an immediate abort. You can use the RMU Monitor Stop command
    to shut down all database activity on your node, optionally
    aborting user processes by forcing an image exit or deleting
    their processes.

    The RMU Monitor Stop command closes the monitor log file also.

    An Oracle Rdb monitor process must be running on a node for
    users logged in to that node to use any Oracle Rdb database.
    In a VMScluster environment, a monitor process must be running on
    each node in the cluster from which databases is accessed.

    The Oracle Rdb monitor process controls all database access and
    initiates the automatic database recovery procedure following a
    system failure or other abnormal termination of a database user
    process. The monitor log file automatically tracks all access to
    the database.