What is alarm suppression?

Overview

The NFM-P is designed to not generate alarms when numerous SNMP traps are sent in quick succession for the same type of event. This prevents alarm storms during intermittent outages in the network caused by bouncing NEs; for example, if links go up and down rapidly. The NFM-P continues to resynchronize the network. If the bouncing NEs continue to send down state SNMP traps, the NFM-P eventually receives the trap and generates the appropriate alarm.

To indicate how often an alarm is generated, the number of occurrences of each instance of the alarm is tracked in the alarm record of the initial alarm. Click on the Statistics tab of an Alarm Info form to display how often the alarm was generated.

To escalate the alarm severity if an alarm reoccurs a specific number of times, use the threshold crossing alert functionality. Configure the escalation or the de-escalation parameter as described in How do I configure alarm policies? .

The NFM-P uses a trap throttling process to prevent the NFM-P system from being overloaded with traps if a failure occurs. Trap throttling does not affect the sequencing of traps. The trap throttling process allows the NFM-P to process traps when time permits. As a result, the NFM-P keeps track of the traps that the software missed and resynchronizes only the missed traps. Trap throttling is supported and configured using the CLI on each Nokia NE. See the NE System Management Guides for configuration information.