Network Address Translation Thresholds


Network Address Translation Thresholds
 
 
Thresholds generate alerts or alarms based on either the total number of Network Address Translation (NAT) calls setup by the system during the specified polling interval, or on the number of currently active calls only.
Alerts or alarms are triggered for call setups based on the following rules:
Enter condition: Actual number of call setups > or = High Threshold
Clear condition: Actual number of call setups < Low Threshold.
If a trigger condition occurs within the polling interval, the alert or alarm will not be generated until the end of the polling interval.
Default value is 0, which means there will be no monitoring.
The polling interval is in seconds and it is an integer between 30 and 60000. Entries will be rounded up to the nearest 30 seconds.
 
Configuring NAT Thresholds
This section describes how to enable and configure NAT thresholds.
 
Enabling Thresholds
To enable thresholds use the following configuration:
configure
  threshold monitoring firewall
  context <context_name>
     threshold monitoring available-ip-pool-group
     end
Notes:
The threshold monitoring available-ip-pool-group command is required only if you are configuring IP pool thresholds. It is not required if you are only configuring NAT port-chunks usage threshold or many-to-one NAT.
 
Configuring Threshold Poll Interval
To configure threshold poll interval use the following configuration:
configure
  threshold poll ip-pool-used interval <interval>
  threshold poll nat-port-chunks-usage interval <interval>
  end
Notes:
The threshold poll nat-port-chunks-usage interval command is only applicable to many-to-one NAT.
 
Configuring Thresholds Limits
To configure threshold limits use the following configuration:
configure
  context<context_name>
     threshold ip-pool-free <high_thresh> [ clear <low_thresh> ]
     ip-pool-hold <high_thresh> [ clear <low_thresh> ]
     ip-pool-release <high_thresh> [ clear <low_thresh> ]
     ip-pool-used <high_thresh> [ clear <low_thresh> ]
     exit
  threshold nat-port-chunks-usage <high_thresh> clear <low_thresh>
  end
Notes:
Thresholds configured using the threshold ip-pool-* commands in the Context Configuration Mode apply to all IP pools in the context
Thresholds configured using the alert-threshold keyword are specific to the pool that they are configured in, and will take priority, i.e. will override the context-wide configuration mentioned above.
 
Saving Your Configuration
When you configure thresholds they are not permanent unless you save the changes. When you have completed configuring thresholds, save your configuration as described in the Verifying and Saving Your Configuration chapter.
 
 

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