display stp process

Function

The display stp process command displays the status of and statistics about the specify ID of a Multiple Spanning Tree Protocol (MSTP) process.

Format

display stp process process-id [ instance instance-id ] [ interface { interface-name | interface-type interface-number } | slot slot-id | vsi vsi-name pw pw-name ] [ brief ]

display stp process process-id [ instance instance-id ] topology-change

display stp process process-id active

display stp process process-id bridge { local | root }

display stp process process-id global

display stp process process-id [ instance instance-id ] abnormal-interface

Parameters

Parameter	Description	Value
process-id	Specifies the ID of a Multiple Spanning Tree Protocol (MSTP) process.	The value is a decimal integer ranging from 1 to 256.
instance instance-id	Displays statistics about the topology changes of a specified STP instance. If instance <instanceId> is not specified, the status of and statistics about all spanning tree instances will be displayed in the sequence of the interface numbers.	The value is an integer ranging from 0 to 4094, Value 0 indicates Common and Internal Spanning Tree (CIST).
interface interface-type interface-number	Displays information of a spanning tree on a specified interface. If interface <ifType> <ifNum> is not specified, the status of and statistics about all interfaces will be displayed in the sequence of the interface numbers.	-
slot slot-id	Specifies the number of the slot where the interface resides.	The value is a string of 1 to 23 case-sensitive characters, spaces not supported.
vsi vsi-name	Specifies the names of a virtual switching instance (VSI).	The vsi-name is a string of 1 to 31 case-sensitive characters, spaces not supported. When quotation marks are used around the string, spaces are allowed in the string.
pw pw-name	Specifies the names of a pseudo wire (PW).	The pw-name is a string of 1 to 15 case-sensitive characters, spaces not supported. When quotation marks are used around the string, spaces are allowed in the string.
brief	Displays the brief status.	-
tc-bpdu	Displays the statistics about sent and received topology change (TC) and topology change notification (TCN) BPDUs on interfaces.	-
statistics	Displays the statistics about sent and received topology change (TC) and topology change notification (TCN) BPDUs on interfaces.	-
topology-change	Displays statistics about Multiple Spanning Tree Protocol (MSTP) topology changes.	-
active	Displays the status of and statistics on spanning trees of all Up interfaces. To view information about spanning trees on all Up interfaces, run the display stp active command.	-
bridge	Displays detailed information about the spanning tree of a bridge. To view detailed information about the spanning trees of the root and local bridges, run the display stp bridge command.	-
local	Displays detailed information about the spanning tree of the local bridge.	-
root	Displays detailed information about the spanning tree of the root bridge.	-
global	Displays global Spanning Tree Protocol (STP) information.	-
abnormal-interface	Displays information about abnormal interfaces running the Spanning Tree Protocol (STP). Run the display stp abnormal-interface command can query information about abnormal STP interfaces quickly.	-

Views

All views

Default Level

1: Monitoring level

Task Name and Operations

Task Name	Operations
mstp	read

Usage Guidelines

Usage Scenario

The display stp process command is used to check whether the spanning tree protocol is run on the existing device or specified interface.
If the Protocol Status field value is Disabled, the spanning tree protocol is not run.
If stp process/Rstp process/Mstp process has been run, information such as the working mode of the spanning tree protocol will be displayed.
The display stp process brief command displays information about spanning trees about the specified ID of a MSTP process, but not global information.
The display stp process global command displays global stp information about the specified ID of a MSTP process.
The display stp process tc-bpdu statistics command displays interface statistics about sent and received topology change and topology change notification BPDUs on the specified ID of a MSTP process.
To determine whether a fault has occurred on interfaces that send and receive TC (Topology Change)/TCN (Topology Change Notification) BPDUs, run display stp process tc-bpdu statistics command to view statistics about sent and received BPDUs. The command output helps you locate the fault.
The display stp process topology-change command displays statistics about MSTP topology changes on the specified ID of a MSTP process.
On a Layer 2 network running Mstp process, a device clears ARP entries and MAC entries after receiving TC BPDUs. If a device receives too many TC BPDUs, the device will frequently clear ARP entries and MAC entries, causing high CPU usage. As a result, network traffic is unstable.
You can run the display stp process topology-change command to display statistics about Mstp process topology changes. If the statistics increase, network flapping occurs.
The display stp process active command displays the status of and statistics on spanning trees of all Up interfaces about the specified ID of a MSTP process.
The display stp process bridge command displays detailed information about the spanning trees of the root and local bridges about the specified ID of a MSTP process.
The display stp process abnormal-interface command displays information about abnormal interfaces running the stp process.

Prerequisites

A process has been configured using the stp process command.

Example

The actual command output varies according to the device. The command output here is only an example.

# Display information about spanning trees on all Up interfaces in MSTP process 0.

<HUAWEI> display stp process 0 active
-------[CIST Global Info][Mode MSTP]-------                                     
CIST Bridge         :61440.00e0-fc12-3456                                       
Config Times        :Hello 2s MaxAge 20s FwDly 15s MaxHop 20                    
Active Times        :Hello 2s MaxAge 20s FwDly 15s MaxHop 20                    
CIST Root/ERPC      :61440.00e0-fc12-3456 / 0                                   
CIST RegRoot/IRPC   :61440.00e0-fc12-3456 / 0                                   
CIST RootPortId     :0.0                                                        
BPDU-Protection     :Disabled                                                   
TC or TCN received  :85                                                         
TC count per hello  :0                                                          
STP Converge Mode   :Normal                                                     
Time since last TC  :0 days 9h:10m:8s
Number of TC        :13                                                         
Last TC occurred    :GigabitEthernet0/1/4                                       
----[Port18(GigabitEthernet0/1/1)][FORWARDING]----                             
 Port Protocol       :Enabled                                                   
 Port Role           :Designated Port                                           
 Port Priority       :128                                                       
 Port Cost(Dot1T )   :Config=auto / Active=20000                                
 Designated Bridge/Port   :61440.00e0-fc12-3456 / 128.18                        
 Port Edged          :Config=default / Active=enabled                           
 Point-to-point      :Config=auto / Active=true                                 
 Transit Limit       :10 packets/s                                              
 Protection Type     :None                                                      
 Port STP Mode       :MSTP                                                      
 Port Protocol Type  :Config=auto / Active=dot1s                                
 BPDU Encapsulation  :Config=stp / Active=stp                                   
 PortTimes           :Hello 2s MaxAge 20s FwDly 15s RemHop 20                   
 TC or TCN send      :5                                                         
 TC or TCN received  :0                                                         
 BPDU Sent           :178445                                                    
          TCN: 0, Config: 0, RST: 0, MST: 178445                                
 BPDU Received       :0                                                         
          TCN: 0, Config: 0, RST: 0, MST: 0                                     
 Last forwarding time: 2012/04/19 16:58:37 UTC+08:00                            
----[Port19(GigabitEthernet0/1/9)][FORWARDING]----                             
 Port Protocol       :Enabled                                                   
 Port Role           :Designated Port                                           
 Port Priority       :128                                                       
 Port Cost(Dot1T )   :Config=auto / Active=20000                                
 Designated Bridge/Port   :61440.00e0-fc12-3456 / 128.19                        
 Port Edged          :Config=default / Active=enabled                           
 Point-to-point      :Config=auto / Active=true                                 
 Transit Limit       :10 packets/s                                              
 Protection Type     :None                                                      
 Port STP Mode       :MSTP                                                      
 Port Protocol Type  :Config=auto / Active=dot1s                                
 BPDU Encapsulation  :Config=stp / Active=stp                                   
 PortTimes           :Hello 2s MaxAge 20s FwDly 15s RemHop 20                   
 TC or TCN send      :0                                                         
 TC or TCN received  :0                                                         
 BPDU Sent           :5                                                         
          TCN: 0, Config: 0, RST: 0, MST: 5                                     
 BPDU Received       :0                                                         
          TCN: 0, Config: 0, RST: 0, MST: 0                                     
 Last forwarding time: 2012/04/23 20:06:08 UTC+08:00                            
                                                                                
-------[MSTI 1 Global Info]-------                                              
MSTI Bridge ID      :61440.00e0-fc12-3456                                       
MSTI RegRoot/IRPC   :61440.00e0-fc12-3456 / 0
MSTI RootPortId     :0.0                                                        
Master Bridge       :61440.00e0-fc12-3456                                       
Cost to Master      :0                                                          
TC received         :2                                                          
TC count per hello  :0                                                          
Time since last TC  :0 days 9h:10m:8s                                           
Number of TC        :9                                                          
Last TC occurred    :GigabitEthernet0/1/4

# Display detailed information about the spanning tree of the root bridge of MSTP process 0.

<HUAWEI> display stp process 0 bridge root
MSTID              Root ID  Root Cost Hello Max Forward Root Port               
                                       Time Age   Delay                         
-------------------------------------------------------------------       
    0 61440.00e0-fc12-3456          0     2  20      15                         
    1 61440.00e0-fc12-3456          0     2  20      15

# Display brief STP information about MSTP process 0.

<HUAWEI> display stp process 0 global
Protocol Status            : Enabled                                            
Bpdu-filter default        : Disabled                                           
Tc-protection              : Disabled                                           
Tc-protection threshold    : 1                                                  
Tc-protection interval     : 2s                                                 
Edged port default         : Enabled                                            
Pathcost-standard          : Dot1t                                              
Timer-factor               : 3                                                  
Transmit-limit             : 10                                                 
Bridge-diameter            : 7                                                  
-------[CIST Global Info][Mode MSTP]-------                                     
CIST Bridge         :61440.00e0-fc12-3456                                       
Config Times        :Hello 2s MaxAge 20s FwDly 15s MaxHop 20                    
Active Times        :Hello 2s MaxAge 20s FwDly 15s MaxHop 20                    
CIST Root/ERPC      :61440.00e0-fc12-3456 / 0                                   
CIST RegRoot/IRPC   :61440.00e0-fc12-3456 / 0                                   
CIST RootPortId     :0.0                                                        
BPDU-Protection     :Disabled                                                   
TC or TCN received  :85                                                         
TC count per hello  :0                                                          
STP Converge Mode   :Normal                                                     
Time since last TC  :0 days 9h:12m:34s                                          
Number of TC        :13                                                         
Last TC occurred    :GigabitEthernet0/1/4

**Table 1** Description of the **display stp process** command output
Item	Description
CIST Bridge Priority	Priority of the switch in CIST.
CIST Global Info	CIST global information.
CIST Bridge	ID of the CIST bridge. The 16 left-most bits are the priority of the switch in CIST. The 48 right-most bits is the MAC address of the switch.
CIST Root/ERPC	CIST root bridge ID/External path cost (path cost from the switch to the CIST root bridge).
CIST RegRoot/IRPC	Region root bridge ID/Internal path cost (path cost from the switch to region root bridge).
CIST RootPortId	CIST root port ID. "0.0" indicates that the switch is a root bridge and has no root port.
Config Times	Values configured manually in the BPDU: Hello: interval at which BPDUs are sent. MaxAge: maximum lifecycle of the BPDU. FwDly: forwarding delay timer. MaxHop: maximum hops in the MST region.
Active Times	Values used actually in the BPDU: Hello: interval at which BPDUs are sent. MaxAge: maximum lifecycle of the BPDU. FwDly: forwarding delay timer. MaxHop: maximum hops in the MST region.
BPDU-Protection	BPDU protection function: disabled. enabled.
TC or TCN received	Number of received topology change (TC) or topology change notification (TCN) BPDUs.
TC count per hello	Number of TC BPDUs received within a hello interval.
TC or TCN send	Number of TC or TCN BPDUs sent by the port.
TC received	Number of received TC BPUDs.
STP Converge Mode	Convergence mode of the spanning tree protocol.
Mode	The operation mode. The default mode is MSTP. For the detailed configuration, see stp mode.
Time since last Topology Change	Time past since the last topology changed.
Time since last TC	Period from the last topology change to now.
Number of Topology Changes	Total number of topology changes since MSTP initialization.
Number of generated topologychange traps	Total number of generated TC traps.
Number of suppressed topologychange traps	Total number of suppressed TC traps.
Number of TC	Number of topology changes.
Last forwarding time	Time when the interface last entered the forwarding state.
Last TC occurred	Last TC occurred.
Port	Interface name.
Port Protocol	The status of the port protocol: enable: STP is enabled on the port. disable: STP is disabled on the port.
Port Role	In a CIST area, the four port roles are as follows: CIST Root Port. CIST Designated Port. CIST Alternate Port. CIST Backup Port.
Port Priority	Priority of the port. For the detailed configuration, see stp port priority.
Port Edged	Status of an edge port that is specified by the administrator. enabled. disabled. Config indicates that the value is configured by using the stp edged-port command. Active indicates the actual value.
Port STP Mode	STP mode on an interface.
Port Protocol Type	Format of the packets that the interface receives and sends: auto. legacy. dot1s. The default value is auto. Config indicates that the packet format is configured using the stp compliance command. Active indicates the actual packet format.
Port Cost(Legacy)	Path cost of the port. It is calculated by dot1t algorithm. config: path cost manually configured. active: actual path cost.
Protocol Status	Status of the protocol.
Protocol Standard	Standards of the protocol.
Designated Bridge/Port	ID of the designated switch and port. The 16 left-most bits of the switch ID represent the priority of the switch in the CIST region; the 48 right-most bits represent the MAC address of the switch. The left-most 4 bits of the port ID represent the priority and the right-most 12 bits represent the port number.
Edged port default	Whether the function of configuring all ports of the switch as edge ports is enabled: Enabled. Disabled.
Point-to-point	Link type of the port. Config indicates that the link type is configured using the stp point-to-point command. Active indicates the actual link type.
Transit Limit	Maximum number of the BPDUs sent by the current port before each Hello time expires. For the detailed configuration, see stp transmit-limit.
Protection Type	Protection type , which can be: None: no protection. LoopBack: self-loop detection. BpduRoot: BPDU and root protection. ROOT: root protection. BPDU: BPDU protection. Loop: loop protection. BpduLoop: BPDU and loop protection.
BPDU Encapsulation	Format of the BPDUs received and sent through a port.
BPDU Sent	Statistics about sent BPDUs: TCN: topology change notification. Config: STP BPDUs. RST: RSTP BPDUs. MST: MSTP BPDUs.
BPDU Received	Statistics about received BPDUs.
MSTI Bridge ID	Multiple Spanning Tree instance (MSTI) bridge ID.
MSTI RootPortId	ID of the MSTI root port. 0.0 indicates that the switch is the root bridge and does not provide any root port.
MSTI RegRoot/IRPC	MSTI root bridge ID/Cost of the internal path (path from the switch to the MSTI root bridge).
Master Bridge	ID of the bridge where the master interface resides. The 16 left-most bits represent the bridge's priority in the CIST. The 48 right-most bits represent the bridge's MAC address.
Cost to Master	Cost of the path from the switch to the bridge where the master interface resides. 0 indicates that the master interface resides on the current bridge.
MSTID	MSTP instance ID.
Root ID	MSTP root bridge ID.
Root Cost	MSTP root path cost.
Root Port	Root port.
Hello time(s)	Interval at which BPDUs are sent from the root bridge.
Hello Time	Interval at which Bridge Protocol Data Units (BPDUs) are sent from the root bridge.
Max hops	Maximum hops in Multiple Spanning Tree (MST) region.
Max age(s)	Maximum lifecycle of the BPDU.
Max Age	Maximum lifetime of a BPDU.
Forward delay(s)	Time interface status transition takes.
Forward Delay	Time interface status transition takes.
Bpdu-filter default	Whether the function of configuring device interfaces as bridge protocol data unit (BPDU) filter interfaces is enabled: Enabled. Disabled.
Tc-protection	Topology change (TC) protection status: Enabled. Disabled.
Tc-protection threshold	Maximum number of TC BPDUs that the MSTP device can process within a specified time.
Tc-protection interval	Time the MSTP device takes to process the maximum number of TC BPDUs.
Pathcost-standard	Method of calculating the MSTP path cost.
Timer-factor	Multiplier of Hello time.
Transmit-limit	Maximum number of BPDUs that the current interface can send each Hello time. For details, see stp transmit-limit.
Bridge-diameter	Network diameter of the MSTP.
TC(Send/Receive)	Statistics about sent and received TC BPDUs.
TCN(Send/Receive)	Statistics about sent and received TCN BPDUs (A hyphen (-) indicates that only MSTI 0 has TCN BPDUs sent and received).
Topology Change initiator(detected)	Interface that triggers a topology change because the interface status changes to Detected.
Topology Change initiator(notified)	Interface that triggers a topology change after receiving a TC BPDU.
Topology Change last received from	Source bridge MAC address contained in a TC BPDU.
Version	Protocol version: 0: STP. 2: RSTP. 3: MSTP.
MAC address	MAC address of the switch.
PortTimes/Port Times	Values in the BPDUs on the interface: Hello: interval at which BPDUs are sent. MaxAge: maximum lifecycle of the BPDU. FwDly: forwarding delay timer. MaxHop: maximum hops in the MST region.