Universal Event Subsystem
Overview
The Universal Event Subsystem (UES) is a subsystem of Universal Enterprise Controller (UEC).
UES provides the means by which event messages, generated by Universal Agent components whenever they perform actions that impact the computing environment on which they execute, are recorded, routed, and managed.
Event Messages
An event message contains information that identifies:
- Source of the event
- Data relating to the event itself
Event messages are collected by Universal Brokers from components that run local to the Brokers. UEC, in turn, collects the event messages from the Brokers and stores them as event records in the UES database (uec.evm.db) for long-term management and access.
Event Types
Examples of event types include:
- Universal Command Server starts a user job, which may be a command, script, or other form of work.
- Universal Broker denies access to a client due to a Universal Access Control List (UACL) denial.
- Universal Data Mover Manager transfers a file from one server to another.
Universal Broker Event Message Processing
Event messages are recorded in the order in which they are received by the Broker. This order is maintained throughout the subsystem.
Note
This order is based on the time that the Broker records the event, not the time that the component generates the event message.
The UES database maintains the event messages generated by local Agent components as event records. The Broker can be stopped and restarted with no loss of event records. The event records remain in the database until the Broker deletes them.
Universal Event Subsystem Activation
UES is not activated by default.
In order to generate and capture event messages, each Agent component that is able to generate event messages has an EVENT_GENERATION option. This option controls which event message types to generate.
By default, EVENT_GENERATION is set so that no event message types are generated. The value must be set so that event messages of interest are generated by the component.
UES Database Clean-up
The UES database continues to accumulate event messages until the Broker deletes them.
Event messages are deleted based upon two criteria:
- Event message expires.
- Event message is delivered to a Universal Enterprise Controller that requested delete access to event messages.
Event message expiration is controlled with the Universal Broker MONITOR_EVENT_EXPIRATION and PERSISTENT_EVENT_EXPIRATION options. These options specify the number of seconds that an event message should remain in the UES database before it is eligible for deletion. Each event message contains the time that it was recorded in the database. The Broker considers an event message expired if the difference between the current time and the recorded time is greater than the option value.
The consequences of this using this method for determining whether or not an event message is expired is that if the value of the option is increased or decreased, the life of all recorded event messages is increased or decreased as well.
UES Database Access
A Broker provides UES database access to UEC. UEC sends a request to a Broker asking for the latest event messages. The Broker responds with event messages that satisfy the UEC request.
The Universal Broker EVENT_ACCESS Universal Access Control List (UACL) entry control read and delete access to the UES database.
The default EVENT_ACCESS rule allows read access and denies delete access. These UACL defaults allow any UEC read access to event messages while denying all UECs delete access to event messages.
An event message becomes eligible for deletion from the Broker UES database once it has been delivered to a UEC that requested delete access. There should be one UEC designated as the production UEC responsible for maintaining the central UES database for all Brokers. This one production UEC should be given delete access on each Broker.