The vSphere alarm infrastructure supports automating actions and sending different types of notification in response to certain server conditions. Many Alarms exist by default on vCenter Server systems. You can also create alarms yourself. For example, an Alarm can send an alert email message when CPU usage on a specific virtual machine exceeds 99% for more than 30 minutes.
The alarm infrastructure integrates with other server components, such as events and performance counters.
The AlarmManager is the service interface for creating, setting, and managing alarms. You create an alarm, specifying trigger conditions and the action to take. When the conditions defined for the Alarm occur on the system, the Action specified for the alarm starts. The alarm also generates an Event that is posted to the Event history database. In addition, the action initiated by the Alarm might also post a second Event to the database, depending on the Action type.
