MSTP/4/TC_GUARDED

Message

MSTP/4/TC_GUARDED: With the TC protection enabled, if TC BPDUs were received after the number of TC BPDUs received by an instance exceeded the threshold, these TC BPDUs were processed after the TC protection time expires. (InstanceID=[InstanceID], bridgePriority=[bridgePriority])

Description

Specify that the instance received TC message exceeded the threshold when TC protection is enabled

Parameters

Parameter Name	Parameter Meaning
InstanceID	Indicates the instance ID.
bridgePriority	Indicates the bridge priority.

Possible Causes

The number of TC messages received by an MSTP process in a specified period exceeded the threshold.

Procedure

1. Check whether the network topology flapping occurs.

If the network topology flapping occurs, go to Step 3.
If the network topology flapping does not occur, go to Step 2.

2. Run the display stp command to check whether the number of TC BPDUs exceeds the set threshold on the interface.

If the number of TC BPDUs exceeds the set threshold on the interface, go to Step 4.
If the number of TC BPDUs does not exceed the set threshold on the interface, go to Step 7.

3. Locate the cause of the network topology flapping and rectify the fault. Then, check whether the alarm is cleared. If the alarm persists, go to Step 2.

4. Run the stp tc-protection threshold threshold command in the system view to reset the maximum number of TC BPDUs that the device can process. Then, check whether the alarm is cleared. If the alarm persists, go to Step 5.

5. Check whether the malicious attack exists.

If the malicious attack exists, go to Step 6.
If the malicious attack does not exist, go to Step 7.

6. Locate the attack source and remove the attack. Then, check whether the alarm is cleared. If the alarm persists, go to Step 7.

7. Collect alarm information and configuration information, and then contact technical support personnel.