Logging Operation

This section discusses operation of the notification-log feature when a notification is generated by the NE.

Logging

When a notification is generated by a NE, it is added to each log that exists in nlmConfigLogTable and satisfies the following conditions:

Before adding a notification to a log, the NE makes sure that the log size limits are not exceeded by this addition in the following manner:

  • For system managed logs (i.e. nlmConfigLogEntryLimit is set to 0):
    • If the total number of entries in all logs combined is equal to the global entry limit (nlmConfigGlobalEntryLimit), then the oldest entry from the system managed log with the largest number of entries is removed before adding the new notification to the log.

Aging

Periodically (every minute), the notification log module calculates the difference between the current time and the time the notification entry is added to a log for each notification entry in each log. If the time difference is greater than the global age out period, the entry is removed from the log. Aging in this manner imposes a limitation that entries may be aged out sooner or later than the actual global age out period if the current time of the NE is changed (for example, to DST changes). Implementing age out accurately consumes 4 additional bytes of memory per notification entry.

Statistics

In ExtremeXOS Release 15.5, the following SNMP Notification Logs statistics are available: