Troubleshooting BPDU Guard
The following procedures provide information to troubleshoot issues with Bridge Protocol Data Unit (BPDU) Guard.
No Packets Received on the Port
For BPDU Guard to work on a port, the port must receive BPDU packets. Perform the following procedure to troubleshoot cases when the port does not receive packets.
Procedure
Example
Port 1/8 receives packets. The remote port is disabled and does not send BPDU packets.
The following example shows that BPDU Guard is enabled for port 1/8. The BPDU Guard administrative state for the port is enabled but the timer counter is 0.
Switch:1>enable Switch:1#show spanning-tree bpduguard 1/8 ======================================================================================== Bpdu Guard ======================================================================================== Port PORT PORT TIMER BPDUGUARD BPDUGUARD NUM MLTID ADMIN_STATE OPER_STATE TIMEOUT COUNT ADMIN_STATE ORIGIN ---------------------------------------------------------------------------- 1/8 Up Up 120 0 Enabled CONFIG Switch:1#show interfaces gigabitEthernet statistics verbose 1/8 ================================================================================================= Port Stats Interface Extended ================================================================================================= PORT_NUM IN_UNICST OUT_UNICST IN_MULTICST OUT_MULTICST IN_BRDCST OUT_BRDCST IN_LSM OUT_LSM ------------------------------------------------------------------------------------------------- 1/8 201 0 160062 60943 4 72 0 0 Switch:1#show spanning-tree mstp port role 1/8 ================================================================================ CIST Port Roles and States ================================================================================ Port-Index Port-Role Port-State PortSTPStatus PortOperStatus -------------------------------------------------------------------------------- 1/8 Disabled Forwarding Disabled Disabled Switch:1#show spanning-tree mstp port statistics 1/8 ================================================================================ MSTP Cist Port Statistics ================================================================================ Port Number : 1/8 Cist Port Fwd Transitions : 0 Cist Port Rx MST BPDUs Count : 0 Cist Port Rx RST BPDUs Count : 0 Cist Port Rx Config BPDUs Count : 0 Cist Port Rx TCN BPDUs Count : 0 Cist Port Tx MST BPDUs Count : 0 Cist Port Tx RST BPDUs Count : 0 Cist Port Tx Config BPDUs Count : 0 Cist Port Tx TCN BPDUs Count : 0 Cist Port Invalid MSTP BPDUs Rx : 0 Cist Port Invalid RST BPDUs Rx : 0 Cist Port Invalid Config BPDUs Rx : 0 Cist Port Invalid TCN BPDUs Rx : 0 Cist Port Proto Migr Count : 0
Variable Definitions
Use the data in the following table to use the show spanning-tree bpduguard command.
Variable |
Value |
---|---|
{slot/port[/sub-port][-slot/port[/sub-port]][,...][slot/all][all]} |
Identifies the
slot and port in one of the following formats:
|
Use the data in the following table to use the show interfaces gigabitEthernet statistics verbose command.
Variable |
Value |
---|---|
{slot/port[/sub-port][-slot/port[/sub-port]][,...][slot/all][all]} |
Identifies the
slot and port in one of the following formats:
|
Use the data in the following table to use the show spanning-tree command.
Variable |
Value |
---|---|
{mstp|rstp} |
Specifies the spanning tree protocol. |
{slot/port[/sub-port][-slot/port[/sub-port]][,...][slot/all][all]} |
Identifies the
slot and port in one of the following formats:
|