What is the alarm purge algorithm?
Overview
Because a large number of outstanding alarms can affect system performance, the NFM-P purges outstanding alarms. The alarm purge algorithm sorts alarms using the following criteria:
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lower severity alarms are deleted before higher severity alarms
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within a severity, the oldest alarms are always deleted first
Note: The alarm purge algorithm is not applied to the following correlating—or root cause—alarms unless the red threshold has been crossed:
When an alarm policy does not exist, the NFM-P purges alarms as follows:
For collocated systems:
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If the outstanding alarm count reaches 45 000, the NFM-P:
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If the outstanding alarm count reaches 60 000, the NFM-P:
For distributed systems:
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If the outstanding alarm count reaches 200 000, the NFM-P:
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If the outstanding alarm count reaches 250 000, the NFM-P:
To ensure that purged alarms are logged, you must enable alarm history logging. See How do I configure alarm history logging? for information about configuring alarm history logging and purging policies.