Event Monitoring and File Triggering - UEMLoad
Overview
A Universal Event Monitor (UEM) Server has three database files that it can use during event processing:
- ueme.db stores event definitions.
- uemh.db stores event handlers.
- uems.db is a spool file that records all activity related to event monitoring.
The UEMLoad utility (uemload) manages the event definition and event handler database files. (For information on the spool database file, see Universal Event Monitor Server.)
UEMLoad can be used to:
- Add, update, and delete event definitions and/or event handlers from their respective database files.
- List the entire contents of the event definition and/or event handler database files.
- List the parameters of a single event definition and/or event handler.
- Export the contents of the event definition and/or event handler database files to a file that can be used to re-initialize the database or populate a new database on another system.
By design, UEMLoad itself only can access local event definition and event handler database files. However, it is possible to store definition load files in a single location (for example, a PDS on a z/OS system) and centrally manage their distribution to remote systems using Universal Command.
When a definition load file is redirected from stdin to Universal Command, Universal Command will in turn forward the redirected stdin to a remote instance of UEMLoad. UEMLoad then behaves as though it were reading a local definition load file.
For detailed information on the event definition and event handler database files, see UEMLoad Utility.
Controlling Database Access
Universal Broker is primarily responsible for providing access to the Universal Agent databases.
However, there are utilities provided, including Universal Spool List (uslist) and Universal Spool Remove (uslrm) that can be used for direct access to these databases. While these utilities should be used only following a recommendation from and with the assistance of Stonebranch, Inc. Customer Support, they are documented in the Universal Agent Utilities 7.3.x Reference Guide.
To protect the database contents, operating system permissions on the database files themselves should be set so that only accounts with super-user or administrative privileges have access to them.
For more information on the location, names, and contents of the UEM database files, see UEM Server Database Files.
Access via UEMLoad Utility
While the contents of UEM databases can be viewed using Universal Spool List, it is recommended that all access be done using the UEMLoad utility.
The ability to remove event definition and event handler records is provided only with UEMLoad. Universal Spool Remove cannot be used to delete records from those databases.
Only UEMLoad can manage event definition and event handler databases that are local to the system on which the UEMLoad resides. To process a request, the UEMLoad sends a message to the Universal Broker running on that system, instructing it to start a demand-driven UEM Server. A control session is established between UEMLoad and the UEM Server, which provides for direct communication between the two processes.
It is over this session that UEMLoad sends the database request to the UEM Server, so that supplied values can be validated and defaults can be provided for any values that were omitted. The UEM Server then forwards the request to the Universal Broker for actual application of the changes to the appropriate database.
UEMLoad executes in the security context of the user account that started it. Since it is the Universal Broker that applies changes to the event definition and event handler databases, any user with the authority to execute UEMLoad will effectively have access to secure resources. It is therefore strongly recommended that the privileges on UEMLoad be set such that only those user accounts with super-user or administrative privileges be allowed to execute it.
Universal Access Control List
Support for controlling access to the event definition and event handler databases also is provided by UEMLoad.
A type of Universal Access Control List (UACL) is provided in order to grant or deny local user accounts the authority to execute UEMLoad. The type of database access (that is: add, update, delete, list, and export) allowed for each authorized user also can be defined.
A typical set of UACL entries intended to fully secure the event definition and event handler databases would include an entry for each user authorized to execute UEMLoad. Then, the types of database access permitted for each of the users would be set in those entries. Finally, a single UACL entry that denies access to all other accounts would be defined.
Whenever UEMLoad is executed, the entries in the UACL will be checked. If a match cannot be found which indicates that the user account that started UEMLoad has the authority to access the database and perform the requested operation, the application will terminate with an error.