Facility Alarms are different from log events. Events are a single point in time and are generally stateless. Facility Alarms have a state (at least two states: active and clear) and duration and can be modeled with state transition events (raised, cleared).
The Facility Alarms module processes log events to generate the raised and cleared state for the alarms. If a raising log event is suppressed under event-control, then the associated alarm will not be raised. If a clearing log event is suppressed under event-control, then it is still processed for the purpose of clearing the associated alarm. Log event filtering, throttling and discarding of events during overload do not affect Facility Alarm processing. Log events are processed by the Facility Alarm module before they are discarded in all cases.
The following figure shows the relationship of log events, alarms and the LEDs.
On platforms that do not support Critical, Major, and Minor LED and Alarm output pins, an event is raised and only a log is generated.
Facility Alarms are different and have independent functionality from other uses of the term "alarm", such as:
configure port ethernet report-alarm
configure system thresholds no memory-use-alarm
configure system thresholds rmon no alarm