The tc-protection threshold command sets the number of times ERPS parses topology change notifications and updates forwarding entries in the topology change protection interval.
The undo tc-protection threshold command restores the default number of times ERPS parses topology change notifications and updates forwarding entries in the topology change protection interval.
By default, ERPS parses topology change notifications and updates forwarding entries three times in the topology change protection interval.
| Parameter | Description | Value |
|---|---|---|
| threshold-value | Specifies the number of times ERPS parses topology change notifications and updates forwarding entries in the topology change protection interval. |
The value is an integer that ranges from 1 to 255. |
Usage Scenario
After a switching device in an ERPS ring network receives topology change notifications, the device updates MAC address entries and ARP entries. Frequent updates will cause a high CPU usage.
To prevent frequent MAC address and ARP entry updates, run the tc-protection threshold command to set the maximum number of topology change notifications that can be processed during the topology change protection interval specified by the tc-protection interval command. Then, during the topology change protection interval, the device processes only the specified maximum number of topology change notification messages. If there are excess notifications, the device processes all the excess notifications once after the topology change protection interval elapses. For example, if the topology change protection interval is set to 10 seconds and the maximum number is set to 5, when a device receives topology change notifications, the device processes only the first 5 topology change notifications within 10 seconds and processes the subsequent topology change notifications only after 10s. This prevents the device from frequently deleting MAC address entries and ARP entries.
Prerequisites
The version v2 command has been run to specify ERPSv2.