Library /sys$common/syshlp/ncphelp.hlb SET, LOGGING, KNOWN_EVENTS  *Conan The Librarian (sorry for the slow response - running on an old VAX)

 Indicates that all events are to be logged to the specified  logging
 component or components.

 The KNOWN EVENTS parameter may be followed by a specific source for
 events (using the CIRCUIT, LINE, or NODE parameters) or a specific
 location for logging these events (using the SINK parameter).  Only
 one source or sink can be specified per command.