display stp

Use display stp to display spanning tree status and statistics. Based on the information, you can analyze and maintain the network topology or determine whether the spanning tree is working correctly.

Syntax

display stp [ instance instance-list | vlan vlan-id-list ] [ interface interface-list | slot slot-number ] [ brief ]

Views

Any view

Predefined user roles

network-admin

network-operator

Parameters

instance instance-list: Specifies a space-separated list of up to 10 MSTI items. Each item specifies an MSTI or a range of MSTIs in the form of instance-id1 [ to instance-id2 ]. The value for instance-id2 must be equal to or greater than the value for instance-id1. The value range for the instance-id argument is 0 to 4094, and the value 0 represents the CIST.

vlan vlan-id-list: Specifies a space-separated list of up to 10 VLAN items. Each item specifies a VLAN or a range of VLANs in the form of vlan-id1 [ to vlan-id2 ]. The value for vlan-id2 must be equal to or greater than the value for vlan-id1. The value range for the vlan-id argument is 1 to 4094.

interface interface-list: Specifies a space-separated list of up to 10 interface items. Each item specifies an interface or a range of interfaces in the form of interface-type interface-number 1 [ to interface-type interface-number 2 ]. The interface number for interface-number 2 must be equal to or greater than the interface number for interface-number 1.

brief: Displays brief spanning tree status and statistics. If this keyword is not specified, the command displays the detailed spanning tree status and statistics.

slot slot-number: Specifies an IRF member device by its member ID. If you do not specify a member device, this command displays spanning tree status and statistics for all member devices.

Usage guidelines

In STP or RSTP mode, the command output is sorted by port name.

If you do not specify a port, this command applies to all ports.
If you specify a port list, this command applies to the specified ports.

In PVST mode, the command output is sorted by VLAN ID and by port name in each VLAN.

If you do not specify a VLAN or port, this command applies to all ports in all VLANs.
If you only specify a VLAN list but not a port, this command applies to all ports in the specified VLANs.
If you only specify a port list but not a VLAN, this command applies to the specified ports in all VLANs.
If you specify both a VLAN list and a port list, this command applies to the ports in the specified VLANs.

In MSTP mode, the command output is sorted by MSTI ID and by port name in each MSTI.

If you do not specify an MSTI or port, this command applies to all MSTIs on all ports.
If you specify an MSTI list but not a port, this command applies to all ports in the specified MSTIs.
If you specify a port list but not an MSTI, this command applies to all MSTIs on the specified ports.
If you specify both an MSTI list and a port list, this command applies to the specified ports in the specified MSTIs.

During network convergence, the most recent spanning tree information is not displayed.

Examples

# In MSTP mode, display the brief spanning tree status and statistics for MSTI 0 on ports Ten-GigabitEthernet 1/0/1 through Ten-GigabitEthernet 1/0/4.

<Sysname> display stp instance 0 interface ten-gigabitethernet 1/0/1 to ten-gigabitethernet 1/0/4 brief
 MST ID      Port                                      Role  STP State     Protection
 0           Ten-GigabitEthernet1/0/1                  ALTE  DISCARDING    LOOP
 0           Ten-GigabitEthernet1/0/2                  DESI  FORWARDING    NONE
 0           Ten-GigabitEthernet1/0/3                  DESI  FORWARDING    NONE
 0           Ten-GigabitEthernet1/0/4                  DESI  FORWARDING    NONE

# In PVST mode, display the brief spanning tree status and statistics for VLAN 2 on ports Ten-GigabitEthernet 1/0/1 through Ten-GigabitEthernet 1/0/4.

<Sysname> system-view
[Sysname] stp mode pvst
[Sysname] display stp vlan 2 interface ten-gigabitethernet 1/0/1 to ten-gigabitethernet 1/0/4 brief
 VLAN ID     Port                                      Role  STP State     Protection
 2           Ten-GigabitEthernet1/0/1                  ALTE  DISCARDING    LOOP
 2           Ten-GigabitEthernet1/0/2                  DESI  FORWARDING    NONE
 2           Ten-GigabitEthernet1/0/3                  DESI  FORWARDING    NONE
 2           Ten-GigabitEthernet1/0/4                  DESI  FORWARDING    NONE

Table 28: Command output

Field	Description
MST ID	MSTI ID in the MST region.
Port	Port name, corresponding to each MSTI or VLAN.
Role	Port role: ALTE—The port is an alternate port. BACK—The port is a backup port. ROOT—The port is a root port. DESI—The port is a designated port. MAST—The port is a master port. DISA—The port is disabled.
STP State	Spanning tree status on the port: FORWARDING—The port can receive and send BPDUs and also forward user traffic. DISCARDING—The port can receive and send BPDUs but cannot forward user traffic. LEARNING—The port is in a transitional state. It can receive and send BPDUs but cannot forward user traffic.
Protection	Effective spanning tree protection feature on the port: ROOT—Root guard. LOOP—Loop guard. BPDU—BPDU guard. NONE—No spanning tree protection feature is configured, or the spanning tree protection is not triggered.

# In MSTP mode, display the detailed spanning tree status and statistics for all MSTIs on all ports.

<Sysname> display stp
-------[CIST Global Info][Mode MSTP]-------
 Bridge ID           : 32768.000f-e200-2200
 Bridge times        : Hello 2s MaxAge 20s FwdDelay 15s MaxHops 20
 Root ID/ERPC        : 0.00e0-fc0e-6554, 200200
 RegRoot ID/IRPC     : 32768.000f-e200-2200, 0
 RootPort ID         : 128.48
 BPDU-Protection     : Disabled
 Bridge Config-
 Digest-Snooping     : Disabled
 TC or TCN received  : 2
 Time since last TC  : 0 days 0h:5m:42s

----[Port153(Ten-GigabitEthernet1/0/1)][FORWARDING]----
 Port protocol       : Enabled
 Port role           : Designated Port (Boundary)
 Port ID             : 128.153
 Port cost(Legacy)   : Config=auto, Active=200
 Desg.bridge/port   : 32768.000f-e200-2200, 128.2
 Port edged          : Config=disabled, Active=disabled
 Point-to-Point      : Config=auto, Active=true
 Transmit limit      : 10 packets/hello-time
 TC-Restriction      : Disabled
 Role-Restriction    : Disabled
 Protection type     : Config=none, Active=none
 MST BPDU format     : Config=auto, Active=legacy
 Port Config-
 Digest-Snooping     : Disabled
 Rapid transition    : False
 Num of VLANs mapped : 1
 Port times          : Hello 2s MaxAge 20s FwdDelay 15s MsgAge 2s RemHops 20
 BPDU sent           : 186
          TCN: 0, Config: 0, RST: 0, MST: 186
 BPDU received       : 0
          TCN: 0, Config: 0, RST: 0, MST: 0

-------[MSTI 1 Global Info]-------
 Bridge ID         : 0.000f-e23e-9ca4
 RegRoot ID/IRPC   : 0.000f-e23e-9ca4, 0
 RootPort ID       : 0.0
 Root type         : Primary root
 Master bridge     : 32768.000f-e23e-9ca4
 Cost to master    : 0
 TC received       : 0

# In PVST mode, display the spanning tree status and statistics for all ports in all VLANs.

<Sysname> system-view
[Sysname] stp mode pvst
[Sysname] display stp
-------[VLAN 1 Global Info]-------
Protocol status     : Enabled
Bridge ID           : 32768.000f-e200-2200
Bridge times        : Hello 2s MaxAge 20s FwdDelay 15s
VlanRoot ID/RPC     : 0.00e0-fc0e-6554, 200200
RootPort ID         : 128.48
BPDU-Protection     : Disabled
TC or TCN received  : 2
Time since last TC  : 0 days 0h:5m:42s

 ----[Port1(Ethernet1/1)][FORWARDING]----
 Port protocol       : Enabled
 Port role           : Designated Port
 Port ID             : 128.153
 Port cost(Legacy)   : Config=auto, Active=200
 Desg. bridge/port   : 32768.000f-e200-2200, 128.2
 Port edged          : Config=disabled, Active=disabled
 Point-to-Point      : Config=auto, Active=true
 Transmit limit      : 10 packets/hello-time
 Protection type     : Config=none, Active=none
 Rapid transition    : False
 Port times          : Hello 2s MaxAge 20s FwdDelay 15s MsgAge 2s

-------[VLAN 2 Global Info]-------
Protocol status      : Enabled
Bridge ID            : 32768.000f-e200-2200
Bridge times         : Hello 2s MaxAge 20s FwDly 15s
VlanRoot ID/RPC      : 0.00e0-fc0e-6554, 200200
RootPort ID          : 128.48
BPDU-Protection      : Disabled
TC or TCN received   : 2
Time since last TC   : 0 days 0h:5m:42s

# In MSTP mode, display the spanning tree status and statistics when the spanning tree feature is disabled.

<Sysname> display stp
 Protocol status    : Disabled
 Protocol Std.      : IEEE 802.1s
 Version            : 3
 Bridge-Prio.  : 32768
 MAC address        : 000f-e200-8048
 Max age(s)         : 20
 Forward delay(s)   : 15
 Hello time(s)      : 2
 Max hops           : 20
 TC Snooping        : Disabled

# In PVST mode, display the spanning tree status and statistics when the spanning tree feature is disabled.

<Sysname> display stp
 Protocol status    : Disabled
 Protocol Std.      : IEEE 802.1w (pvst)
 Version            : 2
 Bridge-Prio.       : 32768
 MAC address        : 3822-d69f-0800
 Max age(s)         : 20
 Forward delay(s)   : 15
 Hello time(s)      : 2
 TC Snooping        : Disabled

Table 29: Command output

Field	Description
Bridge ID	Bridge ID, which contains the device's priority and MAC address. For example, in output 32768.000f-e200-2200, the value preceding the dot is the device's priority. The value following the dot is the device's MAC address.
Bridge times	Major parameters for the bridge: Hello—Hello timer. MaxAge—Maximum age timer. FwdDelay—Forward delay timer. MaxHops—Maximum hops within the MST region.
Root ID/ERPC	CIST root ID and external path cost (the path cost from the device to the CIST root).
RegRoot ID/IRPC	CIST regional root ID and internal path cost (the path cost from the device to the CIST regional root).
VlanRoot ID/RPC	VLAN root ID and root path cost (the path cost from the device to the VLAN root bridge).
RootPort ID	Root port ID. The value 0.0 indicates that the device is the root and there is no root port.
BPDU-Protection	Global status of the BPDU guard function.
Bridge Config- Digest-Snooping	Global status of Digest Snooping.
TC or TCN received	Number of TC/TCN BPDUs received in the MSTI or VLAN.
Time since last TC	Time since the latest topology change in the MSTI or VLAN.
[FORWARDING]	The port is in forwarding state.
[DISCARDING]	The port is in discarding state.
[LEARNING]	The port is in learning state.
Port protocol	Status of the spanning tree feature on the port.
Port role	Port role: Alternate. Backup. Root. Designated. Master. Disabled.
(Boundary)	The port is a regional boundary port.
Port cost(Legacy)	Path cost of the port. The field in parentheses indicates the standard (legacy, dot1d-1998, or dot1t) used for port path cost calculation. Config—Configured value. Active—Actual value.
Desg.bridge/port	Designated bridge ID and port ID of the port. The port ID displayed is insignificant for a port which does not support port priority.
Port edged	The port is an edge port or non-edge port. Config—Configured value. Active—Actual value.
Point-to-Point	The port is connected to a point-to-point link or not. Config—Configured value. Active—Actual value.
Transmit limit	Number of BPDUs sent within each hello time.
Protection type	Whether spanning tree protection is configured on the port: Config—Configured spanning tree protection feature. Active—Effective spanning tree protection feature. Spanning tree protection features are as follows: root—Root guard. loop—Loop guard. bpdu—BPDU guard. none—No spanning tree protection feature is configured, or the spanning tree protection is not triggered.
TC-Restriction	Status of TC transmission restriction on the port.
Role-Restriction	Status of port role restriction on the port.
MST BPDU format	Format of the MST BPDUs that the port can send: Config—Configured value (legacy or 802.1s). Active—Actual value (legacy or 802.1s).
Port Config- Digest-Snooping	Status of Digest Snooping on the port.
Rapid transition	Indicates whether the port rapidly transits to the forwarding state in the MSTI or VLAN.
Num of VLANs mapped	Number of VLANs that are mapped to the MSTI.
Port times	Major parameters for the port: Hello—Hello timer. MaxAge—Maximum age timer. FwdDelay—Forward delay timer. MsgAge—Message age timer. RemHops—Remaining hops.
BPDU sent	Statistics on sent BPDUs.
BPDU received	Statistics on received BPDUs.
RegRoot ID/IRPC	MSTI regional root/internal path cost.
Root Type	MSTI root type: Primary root. Secondary root.
Master bridge	MSTI root bridge ID.
Cost to master	Path cost from the MSTI to the master bridge.
TC received	Number of received TC BPDUs.
Protocol status	Spanning tree protocol status.
Protocol Std.	Spanning tree protocol standard.
Version	Spanning tree protocol version.
Bridge-Prio.	In MSTP mode: Device's priority in the CIST. In PVST mode: Device's priority in VLAN 1.
Max age(s)	Aging timer for BPDUs (in seconds, which is the same as the aging timer for VLAN 1 in PVST mode).
Forward delay(s)	Port state transition delay (in seconds, which is the same as the forward delay for VLAN 1 in PVST mode).
Hello time(s)	Interval for the root bridge to send BPDUs (in seconds, which is the same as the interval for VLAN 1 in PVST mode).
Max hops	Maximum hops in the MSTI.
TC Snooping	Status of TC Snooping, which can be Enabled or Disabled.

Related commands

reset stp

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