MSTP/4/PORT_ROOT_GUARDED

Message

MSTP/4/PORT_ROOT_GUARDED: The root protection port received a superior message. (InstanceID=[InstanceID], PortIndex=[PortIndex], IfIndex=[IfIndex], PortName=[PortName], PwName=[PwName])

Description

Specify that a designated port receives a BPDU packet with the priority higher than that of the root bridge when root bridge protection is enabled

Parameters

Parameter Name	Parameter Meaning
InstanceID	Indicates the instance ID.
PortIndex	MSTP port index.
IfIndex	Indicates the interface index.
PortName	Indicates the port name.
PwName	Indicates the PW name.

Possible Causes

Cause 1: The port that has root protection enabled received BPDUs of higher priorities than that of the bridge. Cause 2: The priorities of some switches changed on the network.

Procedure

Cause 1: The port that has root protection enabled received BPDUs of higher priorities than that of the bridge.

1. Check whether the added physical link is necessary.

If the added physical link is necessary, go to Step 2.
If the added physical link is unnecessary, go to Step 3.

2. Run the display stp [ process ] [ instance instance-id ] [ interface interface-type interface-number | slot slot-id | vsi vsi-name pw ] [ brief ] command to check whether the interfaces are consistent with the STP calculation results.

If the interfaces are consistent with the STP calculation results, no action is required.
If the interfaces are inconsistent with the STP calculation results, go to Step 4.

3. Correctly deploy the network topology, and then check whether the alarm is cleared. If the alarm persists, go to Step 4.

4. Run the display stp [ process ] [ instance instance-id ] [ interface interface-type interface-number | slot slot-id | vsi vsi-name pw ] [ brief ] command to check whether an interface is under the protection of the root bridge.

If an interface is under the protection of the root bridge, go to Step 5.
If no interface is under the protection of the root bridge, go to Step 6.

5. Run the undo stp root-protection command in the interface view to delete the configuration of the protection under the root bridge. Then, check whether the alarm is cleared. If the alarm persists, go to Step 6.

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

Cause 2: The priorities of some switches changed on the network.

1. Run the display stp [ process ] [ instance instance-id ] [ interface interface-type interface-number | slot slot-id | vsi vsi-name pw ] [ brief ] command to check whether the operation of changing the priority is correct.

If the operation is correct, go to Step 3.
If the operation is incorrect, go to Step 2.

2. Run the stp [ instance instance-id ] priority priority command to reset the priority of the local bridge as required. Alternatively, run the undo stp [ instance instance-id ] priority command or the undo stp [ instance instance-id ] root command to restore the default value of the priority of the local bridge. Then, check whether the alarm is cleared. If the alarm persists, go to Step 3.

3. Run the display stp [ process ] [ instance instance-id ] [ interface interface-type interface-number | slot slot-id | vsi vsi-name pw ] [ brief ] command to check whether an interface is under the protection of the root bridge.

If an interface is under the protection of the root bridge, go to Step 4.
If no interface is under the protection of the root bridge, go to Step 5.

4. Run the undo stp root-protection command in the interface view to delete the configuration of the protection under the root bridge. Then, check whether the alarm is cleared. If the alarm persists, go to Step 5.

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