You can configure a threshold rate for receiving TC/TCN packets. If the threshold is exceeded, you receive a warning message. Use the following procedure to display the tc-receive-alarm-threshold configuration.
show spanning-tree tc-receive-alarm-threshold
Switch:1(config)#show spanning-tree tc-receive-alarm-threshold ========================================================================================== Spanning Tree TC/TCN Rx Alarm Threshold Configuration ========================================================================================== Interval : 1 minutes Count : 2