Working with PATROL event classes

This section provides general information about working with PATROL event classes and using them in PATROL KMs.

Why define an event class?

Define a new event class to do one of the following things:

Define an event for which the PATROL standard event classes are unsuitable.
Use event-associated command script (Notification command) to create event-triggered recovery.
Use event-associated command script (Notification command) to trigger user messages.
Use an event-associated command script (Notification command) to log an event as a form of error report.
Set up event-driven processing.

Event-driven processing - unlimited control points

An important feature of PATROL event types is the ability to define a Notification command that executes immediately after the event is triggered. You can use the Notification command to set up event-driven processing, such as performing corrective or diagnostic actions. While a command script in a parameter recovery action has a single control point--the parameter's value, a command script associated with an event type can have many different control points.

Event class programming capsule

This section summarizes typical event class programming. It includes the following topics:

Typical Event Class Algorithms
Event Class Guidelines
Event-Related PSL Functions
Event-Related PATROL Built-in Variables

Typical event class algorithms

The following table lists typical event class algorithms:

Typical event class algorithms

Algorithm	When to use
Send an email to a person or persons.	To notify responsible persons that a specific event has occurred.
Perform a recovery action which can be triggered by the alarming of more than one parameter.	To perform recovery actions triggered by more than one parameter alarm condition.

Event class guidelines

Consider the following guidelines in adding event classes to a PATROL KM.

General

When you define a new event class, add it to the PATROL KM event catalog.

Note

The PATROL Standard Event catalog should be reserved for event classes associated with the core PATROL product - not a specific PATROL KM.

Notification command

If you are using the Notification command to set up complex event-driven actions, carefully consider the frequency that events of the event-class may occur and the effect that the associated PSL scripts could have on PATROL Agent performance.

Event-related PSL functions

The following table lists PSL functions that are often used in working with PATROL events. For more information about PSL functions, refer to the PATROL Script Language Reference Manual.

Event-related PSL functions

PSL function	Definition and usage
event_archive()	Archives PATROL events that match the specified filtering criteria from the Event repository to a specified file.
event_catalog_get()	Returns information about the event catalog. This PSL function has built-in variables that allow you to retrieve the following information for an event class: Text of expert advice SNMP support--whether event class sends SNMP traps Event Description Escalation, notification, and acknowledgment command scripts.
event_check()	Returns the number of events in the PATROL Agent repository that match the specified filtering criteria.
event_query()	Returns a list of the events in the PATROL Agent repository that match the specified filtering criteria.
event_range_manage()	Changes the status of a range of events. Use this function to manage a range of events by changing their statuses.
event_range_query()	Returns a list of the events of a specified event ID range.
event_report()	Returns a statistical report on events in the event repository that match the specified filtering criteria.
event_schedule()	Schedules the execution of an event class' Notification command in the PATROL Agent's main run queue.
event_trigger()	Creates a PATROL event of the specified event class. The implicit origin of the event instance is the PSL context under which the event_trigger() function executed. The event will appear in the PEM. Use this function to develop event reporting within a PATROL KM.
event_trigger2()	Creates a PATROL event of the specified event class. The origin of the event instance is explicitly set by the origin parameter which can be a specific application class or application instance.
remote_event_query()	Returns a list of events in the PEM repository of a remote PATROL Agent that match the specified filter criteria. This function is used in association with the PSL remote_open() function.
remote_event_trigger()	Creates an event instance in the PEM of a remote PATROL Agent. This function assumes that the event catalog and class are already defined in the PEM of the remote PATROL Agent.

Event-related PATROL built-in variables

For event-related PATROL built-in variables that can be used in PSL scripts, see event_query() PSL function.