Storing Event Definitions and Handlers

Overview

Event definitions and event handlers can be stored in separate BerkeleyDB database files. When an event definition or event handler record is added to its respective database, a unique identifier must be specified. Whenever UEM is required to monitor an event or execute an event handler, only this ID needs to be referenced in order for UEM to obtain the corresponding event definition or event handler parameters.

UEMLoad Initiation

UEMLoad initiates all UEM-related database requests. UEMLoad is a command line application that can be used to:

  • Add, update, and delete event definition and/or event handlers from their respective databases
  • List the entire contents of the event definition and/or event handler databases
  • List the parameters of a single event definition and/or event handler
  • Export the contents of the event definition and/or event handler databases to a file that can be used to re-initialize the database or populate a new database on another system.

When UEMLoad is started, it sends a request to a Universal Broker running on the local system to start a UEM Server process. Because a client application (that is, UEMLoad) initiates the request, the UEM Server that is started is a demand-driven Server.

UEMLoad forwards the database request to the UEM Server, which validates it and supplies default values for any required parameters (based upon the type of request) that were not specified from the UEMLoad command line. When a set of complete, valid parameters is available, the UEM Server sends a request to the Universal Broker, which is responsible for actually performing the requested database operation.

Universal Broker Reporting

Universal Broker reports the success or failure of all database maintenance requests (add, update, delete) to the UEM Server. The UEM Server then passes any errors back to UEMLoad.

For a database query request (list, export), Universal Broker will return the contents of each requested event definition or event handler record to the UEM Server, which then is responsible for forwarding the records to the UEMLoad.

UEMLoad Utility Overview

The following figure illustrates the interaction of the Universal Broker and the Universal Event Monitor Server components involved during the execution of UEMLoad.