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This is a critical concept.  The node property will always be the same for any given node.  The element property will be somewhat dynamic, usually a regular expression will parse it.  The most comment element example would be an interface; gig0/0 versus gig0/1.  The stateful property is necessary because the same element may have different events; consider an interface down event versus an OSPF event on the same element (gig0/0).

Example parser for the element property.

                                53 => {
                                        IF => qr/IF-MIB::ifIndex\.\d+=(\d+)/,
                                        THEN => ["capture(element)"],
                                },

Example parser for the stateful property

                                51 => {
                                        IF => qr/IF-MIB::linkDown/,
                                        THEN => ["set.event(Interface Down)", "set.stateful(Interface)",
                                                                         "set.state(down)", "set.priority(3)" ],
                                },

Create Parser Rules

opEvents will process the trap log file as specified on opCommon.nmis.  When parsing the traps the following properties should be extracted.

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