LDAP Event Services utilizes the standard LDAP extension mechanism to expose the eDirectory event system. The LDAP Libraries for Java are enhanced to provide support functions to simplify the use of the event system extension.
The event system extension allows the client to specify the events for which it wants to receive notification. This information is sent in the extension request. If the extension request specifies valid events, the LDAP server keeps the connection open and uses the intermediate extended response to notify the client when events occur. Any data associated with an event is also sent in the response. If an error occurs when processing the extended request or during the subsequent processing of events, the server sends an extended response to the client containing error information and then terminates the processing of the request.
The eDirectory Event System extension is configured on a per LDAP server basis using the iManager utility (for information, see the iManager Documentation). There are two parameters that need to be set. The "allow event monitoring" parameter will turn event monitoring on or off on that particular server. If event monitoring is turned off, the monitor events request will fail. The second parameter is the maximum event monitoring load for the server. A zero value indicates no load limit. Each event type is assigned an integer valued load factor. The load factor is a representation of the loading effect monitoring this event has on the server relative to all other event types. The load is calculated based on each monitored event’s load factor and the number of clients registered for that event.
Any LDAP client can register to monitor any event. Access restrictions are enforced at the time of notification. If the authenticated client does not have access rights to view all of the information in the event, the event will not be sent. The one exception to this rule is the perpetrator DN. If the client does not have rights to the perpertrator object it will be sent as a zero length string. The event notification will still be sent.