- Table of Contents
-
- 05-Network Connectivity Command Reference
- 00-Preface
- 01-MAC address table commands
- 02-Ethernet link aggregation commands
- 03-VLAN commands
- 04-Spanning tree commands
- 05-LLDP commands
- 06-Layer 2 forwarding commands
- 07-PPP commands
- 08-L2TP commands
- 09-ARP commands
- 10-IP addressing commands
- 11-DHCP commands
- 12-DHCPv6 commands
- 13-DNS commands
- 14-NAT commands
- 15-IP performance optimization commands
- 16-IPv6 basics commands
- 17-Tunneling commands
- 18-GRE commands
- 19-ADVPN commands
- 20-Basic IP routing commands
- 21-IP forwarding basics commands
- 22-Static routing commands
- 23-IPv6 static routing commands
- 24-RIP commands
- 25-Policy-based routing commands
- 26-IPv6 policy-based routing commands
- 27-OSPF commands
- 28-RIPng commands
- 29-BGP commands
- 30-IGMP snooping commands
- 31-MLD snooping commands
- Related Documents
-
Title | Size | Download |
---|---|---|
04-Spanning tree commands | 367.82 KB |
Spanning tree commands
active region-configuration
Use active region-configuration to activate your MST region configuration.
Syntax
active region-configuration
Views
MST region view
Predefined user roles
network-admin
Usage guidelines
When you configure MST region parameters, MSTP launches a new spanning tree calculation process that might cause network topology instability. This is most likely to occur when you configure the VLAN-to-instance mapping table. The launch occurs after you execute the active region-configuration command or the stp global enable command.
As a best practice, use the check region-configuration command to determine whether the MST region configurations to be activated are correct. Run this command only when they are correct.
Examples
# Map VLAN 2 to MSTI 1 and activate the MST region configuration.
<Sysname> system-view
[Sysname] stp region-configuration
[Sysname-mst-region] instance 1 vlan 2
[Sysname-mst-region] active region-configuration
Related commands
check region-configuration
instance
region-name
revision-level
stp global enable
vlan-mapping modulo
check region-configuration
Use check region-configuration to display MST region pre-configuration information.
Syntax
check region-configuration
Views
MST region view
Predefined user roles
network-admin
Usage guidelines
Spanning tree devices belong to the same MST region only when they are connected through a physical link and configured with the same details as follows:
· Format selector (0 by default and not configurable).
· MST region name.
· MST region revision level.
· VLAN-to-instance mapping entries in the MST region.
As a best practice, use this command to determine whether the MST region configurations to be activated are correct. Activate them only when they are correct.
Examples
# Display MST region pre-configurations.
<Sysname> system-view
[Sysname] stp region-configuration
[Sysname-mst-region] check region-configuration
Admin Configuration
Format selector : 0
Region name : 001122334400
Revision level : 0
Configuration digest : 0x3ab68794d602fdf43b21c0b37ac3bca8
Instance VLANs Mapped
0 1, 3 to 4094
15 2
Table 1 Command output
Field |
Description |
Format selector |
Format selector of the MST region, which is 0 (not configurable). |
Region name |
MST region name. |
Revision level |
Revision level of the MST region. |
Instance VLANs Mapped |
VLAN-to-instance mappings in the MST region. |
Related commands
active region-configuration
instance
region-name
revision-level
vlan-mapping modulo
display stp
Use display stp to display spanning tree status and statistics.
Syntax
display stp [ instance instance-list | vlan vlan-id-list ] [ interface interface-list ] [ 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 detailed spanning tree status and statistics.
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.
Examples
# In MSTP mode, display the brief spanning tree status and statistics for MSTI 0 on port GigabitEthernet 1/0/1.
<Sysname> display stp instance 0 interface GigabitEthernet 1/0/1 brief
MST ID Port Role STP State Protection
0 0 GigabitEthernet1/0/1 ALTE DISCARDING LOOP
# In PVST mode, display the brief spanning tree status and statistics for VLAN 2 on port GigabitEthernet 1/0/1.
<Sysname> system-view
[Sysname] stp mode pvst
[Sysname] display stp vlan 2 interface gigabitethernet 1/0/1 brief
VLAN ID Port Role STP State Protection
2 GigabitEthernet1/0/1 ALTE DISCARDING LOOP
Table 2 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. If no spanning tree protection feature is configured or spanning tree protection is not triggered, this field displays NONE. |
# 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 : 32768.0001-0000-0000
Bridge times : Hello 2s MaxAge 20s FwdDelay 15s MaxHops 20
Root ID/ERPC : 32768.0001-0000-0000, 0
RegRoot ID/IRPC : 32768.0001-0000-0000, 0
RootPort ID : 0.0
BPDU-Protection : Disabled
Bridge Config-
Digest-Snooping : Disabled
TC or TCN received : 2
Time since last TC : 0 days 0h:0m:58s
----[Port1(GigabitEthernet1/0/1)][FORWARDING]----
Port protocol : Enabled
Port role : Designated Port (Boundary)
Port ID : 128.3
Port cost(Legacy) : Config=auto, Active=200
Desg.bridge/port : 32768.0001-0000-0000, 128.3
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=802.1s
Port Config-
Digest-Snooping : Disabled
Rapid transition : True
Num of VLANs mapped : 0
Port times : Hello 2s MaxAge 20s FwdDelay 15s MsgAge 0s RemHops 20
BPDU sent : 32
TCN: 0, Config: 0, RST: 0, MST: 32
BPDU received : 2
TCN: 0, Config: 0, RST: 0, MST: 2
-------[MSTI 1 Global Info]-------
Bridge ID : 32768.0001-0000-0000
RegRoot ID/IRPC : 32768.0001-0000-0000, 0
RootPort ID : 0.0
Master bridge : 32768.0001-0000-0000
Cost to master : 0
TC received : 0
----[Port1(GigabitEthernet1/0/1)][FORWARDING]----
Port protocol : Enabled
Port role : Designated Port (Boundary)
Port ID : 128.3
Port cost(Legacy) : Config=auto, Active=200
Desg.bridge/port : 32768.0001-0000-0000, 128.3
Protection type : Config=none, Active=none
Rapid transition : True
Num of VLANs mapped : 64
Port times : RemHops 20
# 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(GigabitEthernet1/0/1)][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 3 Command output
Field |
Description |
Bridge ID |
Bridge ID, which contains the device's priority and its 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 feature. |
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. |
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 |
Maximum number of BPDUs sent by a port 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. · PVST BPDU—PVST BPDU guard. If no spanning tree protection feature is configured or spanning tree protection is not triggered, this field displays NONE. |
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 port state transition 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 |
This field is not supported in the current software version. Status of TC Snooping: Enabled or Disabled. |
Related commands
reset stp
display stp abnormal-port
Use display stp abnormal-port to display information about ports that are blocked by spanning tree protection features.
Syntax
display stp abnormal-port
Views
Any view
Predefined user roles
network-admin
network-operator
Examples
# In MSTP mode, display information about ports that are blocked by spanning tree protection features.
<Sysname> display stp abnormal-port
MST ID Blocked Port Reason
1 GigabitEthernet1/0/1 Root-Protected
2 GigabitEthernet1/0/2 Loop-Protected
12 GigabitEthernet1/0/3 Loopback-Protected
# In PVST mode, display information about ports that are blocked by spanning tree protection features.
<Sysname> system-view
[Sysname] stp mode pvst
[Sysname] display stp abnormal-port
VLAN ID Blocked Port Reason
1 GigabitEthernet1/0/1 Root-Protected
2 GigabitEthernet1/0/2 Loop-Protected
2 GigabitEthernet1/0/3 Loopback-Protected
Table 4 Command output
Field |
Description |
MST ID |
MSTI of a blocked port. |
VLAN ID |
VLAN of a blocked port. |
Blocked Port |
Name of a blocked port. |
BlockReason |
Reason that the port was blocked: · Root-Protected—Root guard feature. · Loop-Protected—Loop guard feature. · Loopback-Protected—Self-loop protection. A port in the MSTI receives a BPDU sent by itself. · Disputed—Dispute guard. A port receives a low-priority BPDU from a non-blocked designated port in forwarding or learning state. · InconsistentPortType-Protected—Inconsistent port type protection. · InconsistentPvid-Protected—Inconsistent PVID protection. |
display stp bpdu-statistics
Use display stp bpdu-statistics to display the BPDU statistics for ports.
Syntax
display stp bpdu-statistics [ interface interface-type interface-number [ instance instance-list ] ]
Views
Any view
Predefined user roles
network-admin
network-operator
Parameters
interface interface-type interface-number: Specifies an interface by its type and number.
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.
Usage guidelines
In MSTP mode, the command output is sorted by port name and by MSTI ID on each port.
· If you do not specify an MSTI or port, this command applies to all MSTIs on all ports.
· If you specify a port but not an MSTI, this command applies to all MSTIs on the port.
· If you specify both an MSTI ID and a port, this command applies to the specified MSTI on the port.
In STP, PVST, 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, this command applies to the port.
Examples
# In MSTP mode, display the BPDU statistics for all MSTIs on GigabitEthernet 1/0/1.
<Sysname> display stp bpdu-statistics interface gigabitethernet 1/0/1
Port: GigabitEthernet1/0/1
Instance-Independent:
Type Count Last Updated
--------------------------- ---------- -----------------
Invalid BPDUs 0
Looped-back BPDUs 0
Max-aged BPDUs 0
TCN sent 0
TCN received 0
TCA sent 0
TCA received 2 10:33:12 01/13/2011
Config sent 0
Config received 0
RST sent 0
RST received 0
MST sent 4 10:33:11 01/13/2011
MST received 151 10:37:43 01/13/2011
Instance 0:
Type Count Last Updated
--------------------------- ---------- -----------------
Timeout BPDUs 0
Max-hoped BPDUs 0
TC detected 1 10:32:40 01/13/2011
TC sent 3 10:33:11 01/13/2011
TC received 0
# In PVST mode, display the BPDU statistics for GigabitEthernet 1/0/1.
<Sysname> system-view
[Sysname] stp mode pvst
[Sysname] display stp bpdu-statistics interface gigabitethernet 1/0/1
Port: GigabitEthernet1/0/1
Type Count Last Updated
--------------------------- ---------- -----------------
Invalid BPDUs 0
Looped-back BPDUs 0
Max-aged BPDUs 0
TCN sent 0
TCN received 0
TCA sent 0
TCA received 2 10:33:12 01/13/2010
Config sent 0
Config received 0
RST sent 0
RST received 0
MST sent 4 10:33:11 01/13/2010
MST received 151 10:37:43 01/13/2010
Timeout BPDUs 0
Max-hoped BPDUs 0
TC detected 511 10:32:40 01/13/2010
TC sent 8844 10:33:11 01/13/2010
TC received 1426 10:33:32 01/13/2010
PVID inconsistency BPDUs 0
Table 5 Command output
Field |
Description |
Port |
Port name. |
Instance-Independent |
Statistics not related to a specific MSTI. |
Type |
Statistical item. |
Looped-back BPDUs |
Number of BPDUs sent and then received by the same port. |
Max-aged BPDUs |
Number of BPDUs whose max age was exceeded. |
TCN sent |
Number of sent TCN BPDUs. |
TCN received |
Number of received TCN BPDUs. |
TCA sent |
Number of sent TCA BPDUs. |
TCA received |
Number of received TCA BPDUs. |
Config sent |
Number of sent configuration BPDUs. |
Config received |
Number of received configuration BPDUs. |
RST sent |
Number of sent RSTP BPDUs. |
RST received |
Number of received RSTP BPDUs. |
MST sent |
Number of sent MSTP BPDUs. |
MST received |
Number of received MSTP BPDUs. |
Instance |
Statistics for a specific MSTI. |
Timeout BPDUs |
Number of expired BPDUs. |
Max-hoped BPDUs |
Number of BPDUs whose maximum hops were exceeded. |
TC detected |
Number of detected topology changes. |
TC sent |
Number of sent TC BPDUs. |
TC received |
Number of received TC BPDUs. |
PVID inconsistency BPDUs |
Number of received PVST BPDUs with a PVID inconsistent with the incoming port. |
display stp down-port
Use display stp down-port to display information about ports that were shut down by spanning tree protection features.
Syntax
display stp down-port
Views
Any view
Predefined user roles
network-admin
network-operator
Examples
# Display information about ports that were shut down by spanning tree protection features.
<Sysname> display stp down-port
Down Port Reason
GigabitEthernet1/0/1 BPDU protection
Table 6 Command output
Field |
Description |
Down Port |
Name of a port that was shut down by the spanning tree protection features. |
Reason |
Reason that the port was shut down: · BPDU protection—Indicates the BPDU guard feature. · PVST BPDU protection—Indicates the PVST BPDU guard feature. |
display stp history
Use display stp history to display port role calculation history.
Syntax
display stp [ instance instance-list | vlan vlan-id-list ] history
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.
Usage guidelines
In STP or RSTP mode, the command output is sorted by port role calculation time.
In PVST mode, the command output is sorted by VLAN ID and by port role calculation time in each VLAN.
· If you do not specify a VLAN, this command applies to all VLANs.
· If you specify a VLAN list, this command applies to the specified VLANs.
In MSTP mode, the command output is sorted by MSTI ID and by port role calculation time in each MSTI.
· If you do not specify an MSTI, this command applies to all MSTIs.
· If you specify an MSTI list, this command applies to the specified MSTIs.
Examples
# In STP mode, display the port role calculation history.
<Sysname> display stp history
------------------- Instance 0 ---------------------
Port GigabitEthernet1/0/2
Role change : DESI->ALTE
Time : 2022/08/09 17:44:06
Port priority : 32768.36b5-6d1a-0300 0 32768.36b5-7829-0400 0
32768.36b5-6d1a-0300 128.3 128.3
Designated priority : 32768.36b5-6d1a-0300 20 32768.36b5-7829-0400 0
32768.36b5-7829-0400 128.3 128.3
Port GigabitEthernet1/0/1
Role change : DESI->ROOT
Time : 2022/08/09 17:44:06
Port priority : 32768.36b5-6d1a-0300 0 32768.36b5-7829-0400 0
32768.36b5-6d1a-0300 128.2 128.2
Designated priority : 32768.36b5-6d1a-0300 20 32768.36b5-7829-0400 0
32768.36b5-7829-0400 128.2 128.2
# In MSTP mode, display the port role calculation history for MSTI 2.
<Sysname> display stp instance 2 history
------------------- Instance 2 ---------------------
Port GigabitEthernet1/0/2
Role change : DESI->ALTE
Time : 2022/08/09 16:26:01
Port priority : 0.3085-b8b5-0100 0 0.3085-b8b5-0100 128.3 128.3
Designated priority : 0.3085-b8b5-0100 20 32768.3085-bc3a-0200 128.3 128.3
Port GigabitEthernet1/0/1
Role change : DESI->ROOT
Time : 2022/08/09 16:26:01
Port priority : 0.3085-b8b5-0100 0 0.3085-b8b5-0100 128.2 128.2
Designated priority : 0.3085-b8b5-0100 20 32768.3085-bc3a-0200 128.2 128.2
# In PVST mode, display the port role calculation history for VLAN 2.
<Sysname> display stp vlan 2 history
------------------- VLAN 2 ---------------------
Port GigabitEthernet1/0/2
Role change : DESI->ALTE
Time : 2022/08/09 17:33:39
Port priority : 0.36b5-6d1a-0300 0 0.36b5-6d1a-0300 128.3 128.3
Designated priority : 0.36b5-6d1a-0300 20 32768.36b5-7829-0400 128.3 128.3
Port GigabitEthernet1/0/1
Role change : DESI->ROOT
Time : 2022/08/09 17:33:23
Port priority : 0.36b5-6d1a-0300 0 0.36b5-6d1a-0300 128.2 128.2
Designated priority : 0.36b5-6d1a-0300 20 32768.36b5-7829-0400 128.2 128.2
Table 7 Command output
Field |
Description |
Port |
Port name. |
Role change |
Role change of the port (Aged means that the change was caused by expiration of the received configuration BPDU). |
Time |
Time of port role calculation. |
Port priority |
Current priority of the port: · For STP mode, RSTP mode, and ISTs (MSTI 0) in MSTP mode, port priority includes common root bridge ID, cost of the path to the common root bridge, regional root bridge ID, cost of the path to the regional root bridge, designated bridge ID, designated port ID, and ID of the port that receives messages from the designated port, which are separated with spaces. · For PVST mode and CSTs in MSTP mode, port priority includes regional root bridge ID, cost of the path to the regional root bridge, designated bridge ID, designated port ID, and ID of the port that receives messages from the designated port, which are separated with spaces. |
Designated priority |
Priority information reported by the current port as a designated port: · For STP mode, RSTP mode, and ISTs (MSTI 0) in MSTP mode, port priority includes common root bridge ID, cost of the path to the common root bridge, regional root bridge ID, cost of the path to the regional root bridge, device bridge ID, designated port ID, and current port ID, which are separated with spaces. · For PVST mode and CSTs in MSTP mode, port priority includes regional root bridge ID, cost of the path to the regional root bridge, device bridge ID, designated port ID, and current port ID, which are separated with spaces. |
display stp region-configuration
Use display stp region-configuration to display effective MST region configuration.
Syntax
display stp region-configuration
Views
Any view
Predefined user roles
network-admin
network-operator
Examples
# In MSTP mode, display effective MST region configuration.
<Sysname> display stp region-configuration
Oper Configuration
Format selector : 0
Region name : hello
Revision level : 0
Configuration digest : 0x5f762d9a46311effb7a488a3267fca9f
Instance VLANs Mapped
0 21 to 4094
1 1 to 10
2 11 to 20
Table 8 Command output
Field |
Description |
Format selector |
Format selector that is defined by the spanning tree protocol. The default value is 0, and the selector cannot be configured. |
Region name |
MST region name. |
Revision level |
Revision level of the MST region. The default value is 0, and the level can be configured by using the revision-level command. |
VLANs Mapped |
VLANs mapped to the MSTI. |
Related commands
instance
region-name
revision-level
vlan-mapping modulo
display stp root
Use display stp root to display the root bridge information of spanning trees.
Syntax
display stp root
Views
Any view
Predefined user roles
network-admin
network-operator
Examples
# In MSTP mode, display the root bridge information of all spanning trees.
<Sysname> display stp root
MST ID Root Bridge ID ExtPathCost IntPathCost Root Port
0 0.00e0-fc0e-6554 200200 0 GigabitEthernet1/0/1
# In PVST mode, display the root bridge information of all spanning trees.
<Sysname> display stp root
VLAN ID Root Bridge ID ExtPathCost IntPathCost Root Port
1 0.00e0-fc0e-6554 200200 0 GigabitEthernet1/0/1
Table 9 Command output
Field |
Description |
ExtPathCost |
External path cost. The path cost of a port is either automatically calculated by the device or manually configured by using the stp cost command. |
IntPathCost |
Internal path cost. The path cost of a port is either automatically calculated by the device or manually configured by using the stp cost command. |
Root Port |
Root port name (displayed only if a port of the device is the root port of the MSTI). |
display stp tc
Use display stp tc to display the incoming and outgoing TC/TCN BPDU statistics for ports.
Syntax
display stp [ instance instance-list | vlan vlan-id-list ] tc
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.
Usage guidelines
In STP or RSTP mode, the command output is sorted by port name.
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, this command applies to all VLANs.
· If you specify a VLAN list, this command applies to 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, this command applies to all MSTIs.
· If you specify an MSTI list, this command applies to the specified MSTIs.
Examples
# In MSTP mode, display the incoming and outgoing TC/TCN BPDU statistics for all ports in MSTI 0.
<Sysname> display stp instance 0 tc
MST ID Port Receive Send
0 GigabitEthernet1/0/1 6 4
0 GigabitEthernet1/0/2 0 2
# In PVST mode, display the incoming and outgoing TC/TCN BPDU statistics for all ports in VLAN 2.
<Sysname> display stp vlan 2 tc
VLAN ID Port Receive Send
2 GigabitEthernet1/0/1 6 4
2 GigabitEthernet1/0/2 0 2
Table 10 Command output
Field |
Description |
Port |
Port name. |
Receive |
Number of TC/TCN BPDUs received on a port. |
Send |
Number of TC/TCN BPDUs sent by a port. |
instance
Use instance to map a list of VLANs to an MSTI.
Use undo instance to remap the specified VLAN or all VLANs to the CIST (MSTI 0).
Syntax
instance instance-id vlan vlan-id-list
undo instance instance-id [ vlan vlan-id-list ]
Default
All VLANs are mapped to the CIST.
Views
MST region view
Predefined user roles
network-admin
Parameters
instance-id: Specifies an MSTI ID in the range of 0 to 4094. A value of 0 represents the CIST. The value range for the instance-id argument is 1 to 4094 for the undo instance command.
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.
Usage guidelines
CAUTION: Use caution with global Digest Snooping in the following situations: · When you modify the VLAN-to-instance mappings. · When you restore the default MST region configuration. If the local device has different VLAN-to-instance mappings than its neighboring devices, loops or traffic interruption will occur. |
If you do not specify any VLANs in the undo instance command, all VLANs mapped to the specified MSTI are remapped to the CIST.
You cannot map a VLAN to different MSTIs. If you map a VLAN that has been mapped to an MSTI to a new MSTI, the old mapping is automatically deleted.
You can configure VLAN-to-instance mapping for up to 65 MSTIs.
After configuring this command, run the active region-configuration command to activate the VLAN-to-instance mapping.
Examples
# Map VLAN 2 to MSTI 1.
<Sysname> system-view
[Sysname] stp region-configuration
[Sysname-mst-region] instance 1 vlan 2
Related commands
active region-configuration
check region-configuration
display stp region-configuration
region-name
Use region-name to configure the MST region name.
Use undo region-name to restore the default MST region name.
Default
The MST region name of the device is its MAC address.
Predefined user roles
network-admin
name: Specifies the MST region name, a string of 1 to 32 characters.
The MST region name, the VLAN-to-instance mapping table, and the MSTP revision level of a device determine the device's MST region.
After configuring this command, execute the active region-configuration command to activate the configured MST region name.
# Set the MST region name of the device to hello.
[Sysname] stp region-configuration
[Sysname-mst-region] region-name hello
Related commands
active region-configuration
check region-configuration
display stp region-configuration
instance
revision-level
vlan-mapping modulo
reset stp
Use reset stp to clear the spanning tree statistics.
Syntax
reset stp [ interface interface-list ]
Views
User view
Predefined user roles
network-admin
Parameters
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. If you do not specify this option, this command clears the spanning tree statistics on all ports.
Examples
# Clear the spanning tree statistics on ports GigabitEthernet 1/0/1 through GigabitEthernet 1/0/3.
<Sysname> reset stp interface gigabitethernet 1/0/1 to gigabitethernet 1/0/3
Related commands
display stp
revision-level
Use revision-level to configure the MSTP revision level.
Use undo revision-level to restore the default MSTP revision level.
Syntax
revision-level level
undo revision-level
Default
The MSTP revision level is 0.
Views
MST region view
Predefined user roles
network-admin
Parameters
level: Specifies an MSTP revision level in the range of 0 to 65535.
Usage guidelines
The MSTP revision level, the MST region name, and the VLAN-to-instance mapping table of a device determine the device's MST region.
After configuring this command, execute the active region-configuration command to activate the configured MST region level.
Examples
# Set the MSTP revision level of the MST region to 5.
<Sysname> system-view
[Sysname] stp region-configuration
[Sysname-mst-region] revision-level 5
Related commands
active region-configuration
check region-configuration
display stp region-configuration
instance
region-name
vlan-mapping modulo
snmp-agent trap enable stp
Use snmp-agent trap enable stp to enable SNMP notifications for new-root election events or spanning tree topology changes.
Use undo snmp-agent trap enable stp to disable SNMP notifications for new-root election events or spanning tree topology changes.
Syntax
snmp-agent trap enable stp [ new-root | tc ]
undo snmp-agent trap enable stp [ new-root | tc ]
Default
SNMP notifications are disabled for new-root election events.
In MSTP mode, SNMP notifications are enabled in MSTI 0 and disabled in other MSTIs for spanning tree topology changes.
In PVST mode, SNMP notifications are disabled for spanning tree topology changes in all VLANs.
Views
System view
Predefined user roles
network-admin
Parameters
new-root: Enables the device to send notifications if the device is elected as a new root bridge. This keyword applies only to STP, MSTP, and RSTP modes.
tc: Enables the device to send notifications if the device receives TCN BPDUs. This keyword applies only to PVST mode.
Usage guidelines
If no keyword is specified, the snmp-agent trap enable stp command applies to SNMP notifications for different events as follows:
· In STP, MSTP, and RSTP modes, the command applies to SNMP notifications for new-root election events.
· In PVST mode, the command applies to SNMP notifications for spanning tree topology changes.
Examples
# Enable SNMP notifications for new-root election events.
<Sysname> system-view
[Sysname] snmp-agent trap enable stp new-root
stp bpdu-protection
Use stp bpdu-protection to enable BPDU guard globally.
Use undo stp bpdu-protection to disable BPDU guard globally.
Syntax
stp bpdu-protection
undo stp bpdu-protection
Default
BPDU guard is globally disabled.
Views
System view
Predefined user roles
network-admin
Usage guidelines
With BPDU guard enabled, the device shuts down an edge port and notifies the NMS of the shutdown event when the edge port receives configuration BPDUs.
The device reactivates the ports that have been shut down when the port status detection timer expires. You can set this timer by using the shutdown-interval command. For more information about this command, see device management commands in Device Management Command Reference.
The stp bpdu-protection command takes effect only on the edge ports configured by using the stp edged-port command.
Examples
# Enable BPDU guard globally.
<Sysname> system-view
[Sysname] stp bpdu-protection
Related commands
shutdown-interval(Device Management Command Reference.)
stp edged-port
stp bridge-diameter
Use stp bridge-diameter to set the network diameter. The switched network diameter refers to the maximum number of devices on the path for an edge device to reach another through the root bridge.
Use undo stp bridge-diameter to restore the default.
Syntax
stp [ vlan vlan-id-list ] bridge-diameter diameter
undo stp [ vlan vlan-id-list ] bridge-diameter
Default
The network diameter of the switched network is 7.
Views
System view
Predefined user roles
network-admin
Parameters
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. If you set the STP, RSTP, or MSTP switched network diameter, do not specify this option.
diameter: Specifies the switched network diameter in the range of 2 to 7.
Usage guidelines
An appropriate setting of hello time, forward delay, and max age can speed up network convergence. The values of these timers are related to the network size, and you can set the timers by setting the network diameter. With the network diameter set to 7 (the default), the three timers are also set to their defaults.
In STP, RSTP, or MSTP mode, each MST region is considered as a device. The configured network diameter of the switched network takes effect only on the CIST (or the common root bridge).
In PVST mode, the configured network diameter takes effect only on the root bridges of the specified VLANs.
Examples
# In MSTP mode, set the network diameter of the switched network to 5.
<Sysname> system-view
[Sysname] stp bridge-diameter 5
# In PVST mode, set the network diameter of VLAN 2 in the switched network to 5.
<Sysname> system-view
[Sysname] stp vlan 2 bridge-diameter 5
Related commands
stp timer forward-delay
stp timer hello
stp timer max-age
stp compliance
Use stp compliance to configure the mode a port uses to recognize and send MSTP BPDUs.
Use undo stp compliance to restore the default.
Syntax
stp compliance { auto | dot1s | legacy }
undo stp compliance
Default
A port automatically recognizes the formats of received MSTP packets and determines the formats of MSTP packets to be sent based on the recognized formats.
Views
Layer 2 Ethernet interface view
Layer 2 aggregate interface view
Predefined user roles
network-admin
Parameters
auto: Configures the port to recognize the MSTP BPDU format automatically and determine the format of MSTP BPDUs to send.
dot1s: Configures the port to receive and send only standard-format (802.1s-compliant) MSTP BPDUs.
legacy: Configures the port to receive and send only compatible-format MSTP BPDUs.
Usage guidelines
If this command is configured in Layer 2 Ethernet interface view, it takes effect only on that interface.
If this command is configured in Layer 2 aggregate interface view, it takes effect only on the aggregate interface.
If this command is configured on a member port in an aggregation group, it takes effect only after the port leaves the aggregation group.
Examples
# Configure GigabitEthernet 1/0/1 to send only standard-format (802.1s) MSTP packets.
<Sysname> system-view
[Sysname] interface gigabitethernet 1/0/1
[Sysname-GigabitEthernet1/0/1] stp compliance dot1s
stp config-digest-snooping
Use stp config-digest-snooping to enable Digest Snooping.
Use undo stp config-digest-snooping to disable Digest Snooping.
Syntax
stp config-digest-snooping
undo stp config-digest-snooping
Default
Digest Snooping is disabled.
Views
Layer 2 Ethernet interface view
Layer 2 aggregate interface view
Predefined user roles
network-admin
Usage guidelines
For Digest Snooping to take effect, you must enable Digest Snooping both globally and on associated ports. As a best practice, first enable Digest Snooping on ports connected to third-party vendor devices and then enable the feature globally. Digest Snooping takes effect on the ports simultaneously, which reduces impact on the network.
If this command is configured in Layer 2 Ethernet interface view, it takes effect only on that interface.
If this command is configured in Layer 2 aggregate interface view, it takes effect only on the aggregate interface.
If this command is configured on a member port in an aggregation group, it takes effect only after the port leaves the aggregation group.
Examples
# Enable Digest Snooping on GigabitEthernet 1/0/1 and then globally.
<Sysname> system-view
[Sysname] interface gigabitethernet 1/0/1
[Sysname-GigabitEthernet1/0/1] stp config-digest-snooping
[Sysname-GigabitEthernet1/0/1] quit
[Sysname] stp global config-digest-snooping
Related commands
display stp
stp global config-digest-snooping
stp cost
Use stp cost to set the path cost of a port.
Use undo stp cost to restore the default.
Syntax
stp [ instance instance-list | vlan vlan-id-list ] cost cost-value
undo stp [ instance instance-list | vlan vlan-id-list ] cost
Default
The device automatically calculates the path costs of ports in each spanning tree based on the corresponding standard.
Views
Layer 2 Ethernet interface view
Layer 2 aggregate interface view
Predefined user roles
network-admin
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.
cost-value: Specifies the path cost of the port, with an effective range that varies by path cost calculation standard that is used.
· When the IEEE 802.1d-1998 standard is selected for path cost calculation, the value range for the cost argument is 1 to 65535.
· When the IEEE 802.1t standard is selected for path cost calculation, the value range for the cost argument is 1 to 200000000.
· When the private standard is selected for path cost calculation, the value range for the cost argument is 1 to 200000.
Usage guidelines
Path cost is an important factor in spanning tree calculation. Setting different path costs for a port in MSTIs allows VLAN traffic flows to be forwarded along different physical links. This results in VLAN-based load balancing.
The path cost setting of a port can affect the role selection of the port. When the path cost of a port is changed, the system calculates the role of the port and initiates a state transition.
If this command is configured in Layer 2 Ethernet interface view, it takes effect only on that interface.
If this command is configured in Layer 2 aggregate interface view, it takes effect only on the aggregate interface.
If this command is configured on a member port in an aggregation group, is takes effect only after the port leaves the aggregation group.
If you do not specify an MSTI or VLAN, this command sets the path cost of a port in the MSTP CIST or in the STP or RSTP spanning tree.
Examples
# In MSTP mode, set the path cost to 200 for GigabitEthernet 1/0/1 in MSTI 2.
<Sysname> system-view
[Sysname] interface gigabitethernet 1/0/1
[Sysname-GigabitEthernet1/0/1] stp instance 2 cost 200
# In PVST mode, set the path cost to 200 for GigabitEthernet 1/0/1 in VLAN 2.
<Sysname> system-view
[Sysname] interface gigabitethernet 1/0/1
[Sysname-GigabitEthernet1/0/1] stp vlan 2 cost 200
Related commands
display stp
stp pathcost-standard
stp edged-port
Use stp edged-port to configure a port as an edge port.
Use undo stp edged-port to restore the default.
Syntax
stp edged-port
undo stp edged-port
Default
All ports are non-edge ports.
Views
Layer 2 Ethernet interface view
Layer 2 aggregate interface view
Predefined user roles
network-admin
Usage guidelines
A port directly connecting to a user terminal rather than another device or a shared LAN segment can be configured as an edge port. In case the network topology changes, an edge port does not cause a temporary loop. You can enable the port to transit to the forwarding state rapidly by configuring it as an edge port. As a best practice, configure ports that directly connect to user terminals as edge ports.
Typically, configuration BPDUs from other devices cannot reach an edge port, because the edge port does not connect to any other device. When BPDU guard is disabled on a port configured as an edge port, the port acts as a non-edge port if it receives configuration BPDUs.
On a port, the loop guard feature and the edge port setting are mutually exclusive.
If this command is configured in Layer 2 Ethernet interface view, it takes effect only on that interface.
If this command is configured in Layer 2 aggregate interface view, it takes effect only on the aggregate interface.
If this command is configured on a member port in an aggregation group, it takes effect only after the port leaves the aggregation group.
Examples
# Configure GigabitEthernet 1/0/1 as an edge port.
<Sysname> system-view
[Sysname] interface gigabitethernet 1/0/1
[Sysname-GigabitEthernet1/0/1] stp edged-port
Related commands
stp bpdu-protection
stp loop-protection
stp port bpdu-protection
stp enable
Use stp enable to enable the spanning tree feature.
Use undo stp enable to disable the spanning tree feature.
Syntax
stp enable
undo stp enable
Default
The spanning tree feature is enabled on all ports.
Views
Layer 2 Ethernet interface view
Layer 2 aggregate interface view
Predefined user roles
network-admin
Usage guidelines
When you enable the spanning tree feature, the device operates in STP, RSTP, PVST, or MSTP mode, depending on the spanning tree mode setting.
When you enable the spanning tree feature, the device dynamically maintains the spanning tree status of VLANs, based on received configuration BPDUs. When you disable the spanning tree feature, the device stops maintaining the spanning tree status.
If this command is configured in Layer 2 Ethernet interface view, it takes effect only on that interface.
If this command is configured in Layer 2 aggregate interface view, it takes effect only on the aggregate interface.
If this command is configured on a member port in an aggregation group, it takes effect only after the port leaves the aggregation group.
Examples
# In MSTP mode, disable the spanning tree feature on GigabitEthernet 1/0/1.
<Sysname> system-view
[Sysname] interface gigabitethernet 1/0/1
[Sysname-GigabitEthernet1/0/1] undo stp enable
Related commands
stp global enable
stp mode
stp vlan enable
stp global config-digest-snooping
Use stp global config-digest-snooping to enable Digest Snooping globally.
Use undo stp global config-digest-snooping to disable Digest Snooping globally.
Syntax
stp global config-digest-snooping
undo stp global config-digest-snooping
Default
Digest Snooping is disabled globally.
Views
System view
Predefined user roles
network-admin
Usage guidelines
For Digest Snooping to take effect, you must enable Digest Snooping both globally and on associated ports. As a best practice, first enable Digest Snooping on ports connected to third-party vendor devices and then enable the feature globally. Digest Snooping takes effect on the ports simultaneously, which reduces impact on the network.
Examples
# Enable Digest Snooping on GigabitEthernet 1/0/1 and then globally.
<Sysname> system-view
[Sysname] interface gigabitethernet 1/0/1
[Sysname-GigabitEthernet1/0/1] stp config-digest-snooping
[Sysname-GigabitEthernet1/0/1] quit
[Sysname] stp global config-digest-snooping
Related commands
display stp
stp config-digest-snooping
stp global enable
Use stp global enable to enable the spanning tree feature globally.
Use undo stp global enable to disable the spanning tree feature globally.
Syntax
stp global enable
undo stp global enable
Default
The spanning tree feature is disabled globally.
Views
System view
Predefined user roles
network-admin
Usage guidelines
When you enable the spanning tree feature, the device operates in STP, RSTP, PVST, or MSTP mode, depending on the spanning tree mode setting.
When the spanning tree feature is enabled, the device dynamically maintains the spanning tree status of VLANs based on received configuration BPDUs. When the spanning tree feature is disabled, the device stops maintaining the spanning tree status.
Examples
# Enable the spanning tree feature globally.
<Sysname> system-view
[Sysname] stp global enable
Related commands
stp enable
stp mode
stp global mcheck
Use stp global mcheck to perform mCheck globally.
Syntax
stp global mcheck
Views
System view
Predefined user roles
network-admin
Usage guidelines
When a port on an MSTP, RSTP, or PVST device connects to an STP device and receives STP BPDUs, the port automatically transits to the STP mode. However, the port cannot automatically transit back to the original mode when the following conditions exist:
· The peer STP device is shut down or removed.
· The port cannot detect the change.
In this case, you can perform an mCheck operation to forcibly transit the port to operate in the original mode.
The device operates in STP, RSTP, PVST, or MSTP mode, depending on the spanning tree mode setting.
The stp global mcheck command takes effect only when the device operates in MSTP, RSTP, or PVST mode.
Examples
# Perform mCheck globally.
<Sysname> system-view
[Sysname] stp global mcheck
Related commands
stp mcheck
stp mode
stp ignore-pvid-inconsistency
Use stp ignore-pvid-inconsistency to disable inconsistent PVID protection.
Use undo stp ignore-pvid-inconsistency to enable inconsistent PVID protection.
Syntax
stp ignore-pvid-inconsistency
undo stp ignore-pvid-inconsistency
Default
Inconsistent PVID protection is enabled.
Views
System view
Predefined user roles
network-admin
Usage guidelines
This command takes effect only when the device is operating in PVST mode.
Disabling inconsistent PVID protection might cause spanning tree calculation errors. To avoid such errors, make sure the following requirements are met:
· Make sure the VLANs on one device do not use the same ID as the PVID of its peer port (except the default VLAN) on another device.
· If the local port or its peer is a hybrid port, do not configure the local and peer ports as untagged members of the same VLAN.
· Disable inconsistent PVID protection on both the local device and the peer device.
Examples
# In PVST mode, disable the inconsistent PVID protection feature.
<Sysname> system-view
[Sysname] stp mode pvst
[Sysname] stp ignore-pvid-inconsistency
stp loop-protection
Use stp loop-protection to enable loop guard on a port.
Use undo stp loop-protection to disable loop guard on a port.
Syntax
stp loop-protection
undo stp loop-protection
Default
Loop guard is disabled.
Views
Layer 2 Ethernet interface view
Layer 2 aggregate interface view
Predefined user roles
network-admin
Usage guidelines
On a port, the loop guard feature is mutually exclusive with the root guard feature or the edge port setting.
If this command is configured in Layer 2 Ethernet interface view, it takes effect only on that interface.
If this command is configured in Layer 2 aggregate interface view, it takes effect only on the aggregate interface.
If this command is configured on a member port in an aggregation group, it takes effect only after the port leaves the aggregation group.
Examples
# Enable loop guard on GigabitEthernet 1/0/1.
<Sysname> system-view
[Sysname] interface gigabitethernet 1/0/1
[Sysname-GigabitEthernet1/0/1] stp loop-protection
Related commands
stp edged-port
stp root-protection
stp max-hops
Use stp max-hops to set the maximum number of hops for an MST region.
Use undo stp max-hops to restore the default.
Syntax
stp max-hops hops
undo stp max-hops
Default
The maximum number of hops for an MST region is 20.
Views
System view
Predefined user roles
network-admin
Parameters
hops: Specifies the maximum hops in the range of 1 to 40.
Examples
# Set the maximum hops of the MST region to 35.
<Sysname> system-view
[Sysname] stp max-hops 35
Related commands
display stp
stp mcheck
Use stp mcheck to perform mCheck on a port.
Syntax
stp mcheck
Views
Layer 2 Ethernet interface view
Layer 2 aggregate interface view
Predefined user roles
network-admin
Usage guidelines
When a port on an MSTP, RSTP, or PVST device connects to an STP device and receives STP BPDUs, the port automatically transits to the STP mode. However, the port cannot automatically transit back to the original mode when the following conditions exist:
· The peer STP device is shut down or removed.
· The port cannot detect the change.
In this case, you can perform an mCheck operation to forcibly transit the port to operation in the original mode.
For example, Device A, Device B, and Device C are connected in sequence. Device A runs STP, Device B does not run any spanning tree protocol, and Device C runs RSTP, MSTP, or PVST. When Device C receives an STP BPDU transparently transmitted by Device B, the receiving port transits to the STP mode. If you configure Device B to run RSTP, MSTP, or PVST with Device C, perform mCheck operations on the ports that connect Device B and Device C.
The device operates in STP, RSTP, PVST, or MSTP mode, depending on the spanning tree mode setting.
The stp mcheck command takes effect only when the device operates in MSTP, RSTP, or PVST mode.
If this command is configured in Layer 2 Ethernet interface view, it takes effect only on that interface.
If this command is configured in Layer 2 aggregate interface view, it takes effect only on the aggregate interface.
If this command is configured on a member port in an aggregation group, it takes effect only after the port leaves the aggregation group.
Examples
# Perform mCheck on GigabitEthernet 1/0/1.
<Sysname> system-view
[Sysname] interface gigabitethernet 1/0/1
[Sysname-GigabitEthernet1/0/1] stp mcheck
Related commands
stp global mcheck
stp mode
stp mode
Use stp mode to configure the spanning tree operating mode.
Use undo stp mode to restore the default.
Syntax
stp mode { mstp | pvst | rstp | stp }
undo stp mode
Default
A spanning tree device operates in MSTP mode.
Views
System view
Predefined user roles
network-admin
Parameters
mstp: Configures the spanning tree device to operate in MSTP mode.
pvst: Configures the spanning tree device to operate in PVST mode.
rstp: Configures the spanning tree device to operate in RSTP mode.
stp: Configures the spanning tree device to operate in STP mode.
Usage guidelines
The MSTP mode is compatible with the RSTP mode, and the RSTP mode is compatible with the STP mode.
The PVST mode's compatibility with other modes is as follows:
· Access port—The PVST mode is compatible with other modes in any VLAN.
· Trunk or hybrid port—The PVST mode is compatible with other modes only in the default VLAN.
Examples
# Configure the spanning tree device to operate in STP mode.
<Sysname> system-view
[Sysname] stp mode stp
Related commands
stp enable
stp global enable
stp global mcheck
stp vlan enable
stp no-agreement-check
Use stp no-agreement-check to enable No Agreement Check on a port.
Use undo stp no-agreement-check to disable No Agreement Check on a port.
Syntax
stp no-agreement-check
undo stp no-agreement-check
Default
No Agreement Check is disabled.
Views
Layer 2 Ethernet interface view
Layer 2 aggregate interface view
Predefined user roles
network-admin
Usage guidelines
This command takes effect only after you enable it on the root port.
If this command is configured in Layer 2 Ethernet interface view, it takes effect only on that interface.
If this command is configured in Layer 2 aggregate interface view, it takes effect only on the aggregate interface.
If this command is configured on a member port in an aggregation group, it takes effect only after the port leaves the aggregation group.
Examples
# Enable No Agreement Check on GigabitEthernet 1/0/1.
<Sysname> system-view
[Sysname] interface gigabitethernet 1/0/1
[Sysname-GigabitEthernet1/0/1] stp no-agreement-check
stp pathcost-standard
Use stp pathcost-standard to specify a standard for the device to use when calculating the default path costs for ports.
Use undo stp pathcost-standard to restore the default.
Syntax
stp pathcost-standard { dot1d-1998 | dot1t | legacy }
undo stp pathcost-standard
Default
The default standard is legacy.
Views
System view
Predefined user roles
network-admin
Parameters
dot1d-1998: Configures the device to calculate the default path cost for ports based on IEEE 802.1d-1998.
dot1t: Configures the device to calculate the default path cost for ports based on IEEE 802.1t.
legacy: Configures the device to calculate the default path cost for ports based on a private standard.
Usage guidelines
If you change the standard that the device uses in calculating the default path costs, you restore the path costs to the default.
Examples
# Configure the device to calculate the default path cost for ports based on IEEE 802.1d-1998.
<Sysname> system-view
[Sysname] stp pathcost-standard dot1d-1998
Related commands
display stp
stp cost
stp point-to-point
Use stp point-to-point to configure the link type of a port.
Use undo stp point-to-point to restore the default.
Syntax
stp point-to-point { auto | force-false | force-true }
undo stp point-to-point
Default
The default setting is auto, and the spanning tree device automatically detects whether a port connects to a point-to-point link.
Views
Layer 2 Ethernet interface view
Layer 2 aggregate interface view
Predefined user roles
network-admin
Parameters
auto: Specifies automatic detection of the link type.
force-false: Specifies the non-point-to-point link type.
force-true: Specifies the point-to-point link type.
Usage guidelines
When connecting to a non-point-to-point link, a port is incapable of rapid state transition.
You can configure the link type as point-to-point for a Layer 2 aggregate interface or a port that operates in full duplex mode. As a best practice, use the default setting to let the device automatically detect the port link type.
In MSTP or PVST mode, the stp point-to-point force-false or stp point-to-point force-true command configured on a port takes effect on all MSTIs or VLANs.
Before you set the link type of a port to point-to-point, make sure the port is connected to a point-to-point link. Otherwise, a temporary loop might occur.
If this command is configured in Layer 2 Ethernet interface view, it takes effect only on that interface.
If this command is configured in Layer 2 aggregate interface view, it takes effect only on the aggregate interface.
If this command is configured on a member port in an aggregation group, it takes effect only after the port leaves the aggregation group.
Examples
# Configure the link type of GigabitEthernet 1/0/1 as point-to-point.
<Sysname> system-view
[Sysname] interface gigabitethernet 1/0/1
[Sysname-GigabitEthernet1/0/1] stp point-to-point force-true
Related commands
display stp
stp port priority
Use stp port priority to set the priority of a port. The port priority affects the role of a port in a spanning tree.
Use undo stp port priority to restore the default.
Syntax
stp [ instance instance-list | vlan vlan-id-list ] port priority priority
undo stp [ instance instance-list | vlan vlan-id-list ] port priority
Default
The port priority is 128.
Views
Layer 2 Ethernet interface view
Layer 2 aggregate interface view
Predefined user roles
network-admin
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.
priority: Specifies the port priority in the range of 0 to 240 in increments of 16 (as in 0, 16, 32).
Usage guidelines
The smaller the value, the higher the port priority. If all ports on your device use the same priority value, the port priority depends on the port index. The smaller the index, the higher the priority.
If this command is configured in Layer 2 Ethernet interface view, it takes effect only on that interface.
If this command is configured in Layer 2 aggregate interface view, it takes effect only on the aggregate interface.
If this command is configured on a member port in an aggregation group, it takes effect only after the port leaves the aggregation group.
If you do not specify an MSTI or VLAN, this command configures the priority of the ports in the MSTP CIST or in the STP or RSTP spanning tree.
Examples
# In MSTP mode, set the port priority of GigabitEthernet 1/0/1 to 16 in MSTI 2.
<Sysname> system-view
[Sysname] interface gigabitethernet 1/0/1
[Sysname-GigabitEthernet1/0/1] stp instance 2 port priority 16
# In PVST mode, set the port priority of GigabitEthernet 1/0/1 to 16 in VLAN 2.
<Sysname> system-view
[Sysname] interface gigabitethernet 1/0/1
[Sysname-GigabitEthernet1/0/1] stp vlan 2 port priority 16
Related commands
display stp
stp port-log
Use stp port-log to enable outputting port state transition information.
Use undo stp port-log to disable outputting port state transition information.
Syntax
stp port-log { all | instance instance-list | vlan vlan-id-list }
undo stp port-log { all | instance instance-list | vlan vlan-id-list }
Default
Outputting port state transition information is disabled.
Views
System view
Predefined user roles
network-admin
Parameters
all: Specifies all MSTIs or VLANs.
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.
Examples
# In MSTP mode, enable outputting port state transition information for MSTI 2.
<Sysname> system-view
[Sysname] stp port-log instance 2
%Aug 16 00:49:41:856 2011 Sysname STP/3/STP_DISCARDING: Instance 2's port GigabitEthernet1/0/1 has been set to discarding state.
%Aug 16 00:49:41:856 2011 Sysname STP/3/STP_FORWARDING: Instance 2's port GigabitEthernet1/0/2 has been set to forwarding state.
The output shows that GigabitEthernet 1/0/1 in MSTI 2 transited to the discarding state and GigabitEthernet 1/0/2 in MSTI 2 transited to the forwarding state.
# In PVST mode, enable outputting port state transition information for VLAN 1 through VLAN 4094.
<Sysname> system-view
[Sysname] stp port-log vlan 1 to 4094
%Aug 16 00:49:41:856 2006 Sysname STP/3/STP_DISCARDING: VLAN 2's GigabitEthernet1/0/1 has been set to discarding state.
%Aug 16 00:49:41:856 2006 Sysname STP/3/STP_FORWARDING: VLAN 2's GigabitEthernet1/0/2 has been set to forwarding state.
The output shows that GigabitEthernet 1/0/1 in VLAN 2 transited to the discarding state and GigabitEthernet 1/0/2 in VLAN 2 transited to the forwarding state.
stp priority
Use stp priority to set the priority of the device.
Use undo stp priority to restore the default.
Syntax
stp [ instance instance-list | vlan vlan-id-list ] priority priority
undo stp [ instance instance-list | vlan vlan-id-list ] priority
Default
The device priority is 32768.
Views
System view
Predefined user roles
network-admin
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.
priority: Specifies the device priority in the range of 0 to 61440 in increments of 4096 (as in 0, 4096, 8192). You can set up to 16 priority values on the device. The smaller the value, the higher the device priority.
Usage guidelines
If you do not specify an MSTI or VLAN, this command configures the priority of the device in the MSTP CIST or in the STP or RSTP spanning tree.
Examples
# In MSTP mode, set the device priority to 4096 in MSTI 1.
<Sysname> system-view
[Sysname] stp instance 1 priority 4096
# In PVST mode, set the device priority to 4096 in VLAN 1.
<Sysname> system-view
[Sysname] stp vlan 1 priority 4096
stp pvst-bpdu-protection
Use stp pvst-bpdu-protection to enable PVST BPDU guard.
Use undo stp pvst-bpdu-protection to disable PVST BPDU guard.
Syntax
stp pvst-bpdu-protection
undo stp pvst-bpdu-protection
Default
PVST BPDU guard is disabled.
Views
System view
Predefined user roles
network-admin
Usage guidelines
PVST BPDU guard enables an MSTP-enabled device to shut down a port if the port receives PVST BPDUs. The shutdown port is brought up after a detection timer expires. To set the detection timer, use the shutdown-interval command.
Examples
# In MSTP mode, enable PVST BPDU guard.
<Sysname> system-view
[Sysname] stp pvst-bpdu-protection
Related commands
shutdown-interval (For more information, see System Management Command Reference.)
stp region-configuration
Use stp region-configuration to enter MST region view.
Use undo stp region-configuration to restore the default MST region configurations.
Syntax
stp region-configuration
undo stp region-configuration
Default
The default settings for an MST region are as follows:
· The MST region name of the device is its MAC address.
· All VLANs are mapped to the CIST.
· The MSTP revision level is 0.
Views
System view
Predefined user roles
network-admin
Usage guidelines
After you enter MST region view, you can configure MST region parameters, including the region name, VLAN-to-instance mappings, and revision level.
Examples
# Enter MST region view.
<Sysname> system-view
[Sysname] stp region-configuration
[Sysname-mst-region]
stp role-restriction
Use stp role-restriction to enable port role restriction.
Use undo stp role-restriction to disable port role restriction.
Syntax
stp role-restriction
undo stp role-restriction
Default
Port role restriction is disabled.
Views
Layer 2 Ethernet interface view
Layer 2 aggregate interface view
Predefined user roles
network-admin
Usage guidelines
When port role restriction is enabled on a port, the port cannot become a root port.
If this command is configured in Layer 2 Ethernet interface view, it takes effect only on that interface.
If this command is configured in Layer 2 aggregate interface view, it takes effect only on the aggregate interface.
If this command is configured on a member port in an aggregation group, it takes effect only after the port leaves the aggregation group.
Examples
# Enable port role restriction on GigabitEthernet 1/0/1.
<Sysname> system-view
[Sysname] interface gigabitethernet 1/0/1
[Sysname-GigabitEthernet1/0/1] stp role-restriction
stp root primary
Use stp root primary to configure the device as the root bridge.
Use undo stp root to restore the default.
Syntax
stp [ instance instance-list | vlan vlan-id-list ] root primary
undo stp [ instance instance-list | vlan vlan-id-list ] root
Default
The device is not a root bridge.
Views
System view
Predefined user roles
network-admin
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.
Usage guidelines
Once you specify the device as the root bridge, you cannot change the priority of the device.
If you do not specify an MSTI or VLAN, this command configures the device as the root bridge of the MSTP CIST or of the STP or RSTP spanning tree.
Examples
# In MSTP mode, specify the device as the root bridge of MSTI 1.
<Sysname> system-view
[Sysname] stp instance 1 root primary
# In PVST mode, specify the device as the root bridge of VLAN 1.
<Sysname> system-view
[Sysname] stp vlan 1 root primary
Related commands
stp priority
stp root secondary
stp root secondary
Use stp root secondary to configure the device as a secondary root bridge.
Use undo stp root to restore the default.
Syntax
stp [ instance instance-list | vlan vlan-id-list ] root secondary
undo stp [ instance instance-list | vlan vlan-id-list ] root
Default
The device is not a secondary root bridge.
Views
System view
Predefined user roles
network-admin
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.
Usage guidelines
Once you specify the device as a secondary root bridge, you cannot change the priority of the device.
If you do not specify an MSTI or VLAN, this command configures a secondary root bridge for the MSTP CIST or the STP or RSTP spanning tree.
Examples
# In MSTP mode, specify the device as a secondary root bridge in MSTI 1.
<Sysname> system-view
[Sysname] stp instance 1 root secondary
# In PVST mode, specify the device as a secondary root bridge in VLAN 1.
<Sysname> system-view
[Sysname] stp vlan 1 root secondary
Related commands
stp priority
stp root primary
stp root-protection
Use stp root-protection to enable root guard on a port.
Use undo stp root-protection to disable root guard on a port.
Syntax
stp root-protection
undo stp root-protection
Default
Root guard is disabled.
Views
Layer 2 Ethernet interface view
Layer 2 aggregate interface view
Predefined user roles
network-admin
Usage guidelines
On a port, the loop guard feature and the root guard feature are mutually exclusive.
If this command is configured in Layer 2 Ethernet interface view, it takes effect only on that interface.
If this command is configured in Layer 2 aggregate interface view, it takes effect only on the aggregate interface.
If this command is configured on a member port in an aggregation group, it takes effect only after the port leaves the aggregation group.
Examples
# Enable root guard on GigabitEthernet 1/0/1.
<Sysname> system-view
[Sysname] interface gigabitethernet 1/0/1
[Sysname-GigabitEthernet1/0/1] stp root-protection
Related commands
stp edged-port
stp loop-protection
stp tc-protection
Use stp tc-protection to enable TC-BPDU attack guard for the device.
Use undo stp tc-protection to disable TC-BPDU attack guard for the device.
Syntax
stp tc-protection
undo stp tc-protection
Default
TC-BPDU attack guard is enabled.
Views
System view
Predefined user roles
network-admin
Usage guidelines
With TC-BPDU guard, you can set the maximum number of immediate forwarding address entry flushes that the device can perform every 10 seconds. For TC-BPDUs received that exceed the limit, the device performs a forwarding address entry flush when the interval elapses. This prevents frequent flushing of forwarding address entries.
Examples
# Disable TC-BPDU attack guard for the device.
<Sysname> system-view
[Sysname] undo stp tc-protection
Related commands
stp tc-protection threshold
stp tc-protection threshold
Use stp tc-protection threshold to set the maximum number of forwarding address entry flushes that the device can perform every 10 seconds.
Use undo stp tc-protection threshold to restore the default.
Syntax
stp tc-protection threshold number
undo stp tc-protection threshold
Default
By default, the device can perform a maximum of 6 forwarding address entry flushes every 10 seconds.
Views
System view
Predefined user roles
network-admin
Parameters
number: Specifies the maximum number of immediate forwarding address entry flushes that the device can perform every 10 seconds. The value is in the range of 1 to 255.
Examples
# Configure the device to perform up to 10 forwarding address entry flushes every 10 seconds.
<Sysname> system-view
[Sysname] stp tc-protection threshold 10
Related commands
stp tc-protection
stp tc-restriction
Use stp tc-restriction to enable TC-BPDU transmission restriction.
Use undo stp tc-restriction to disable TC-BPDU transmission restriction.
Syntax
stp tc-restriction
undo stp tc-restriction
Default
TC-BPDU transmission restriction is disabled.
Views
Layer 2 Ethernet interface view
Layer 2 aggregate interface view
Predefined user roles
network-admin
Usage guidelines
When TC-BPDU transmission restriction is enabled on a port, the port does not send TC-BPDUs to other ports. It also does not delete MAC address entries.
If this command is configured in Layer 2 Ethernet interface view, it takes effect only on that interface.
If this command is configured in Layer 2 aggregate interface view, it takes effect only on the aggregate interface.
If this command is configured on a member port in an aggregation group, it takes effect only after the port leaves the aggregation group.
Examples
# Enable TC-BPDU transmission restriction on GigabitEthernet 1/0/1.
<Sysname> system-view
[Sysname] interface gigabitethernet 1/0/1
[Sysname-GigabitEthernet1/0/1] stp tc-restriction
stp tc-snooping
Use stp tc-snooping to enable TC Snooping.
Use undo stp tc-snooping to disable TC Snooping.
Syntax
stp tc-snooping
undo stp tc-snooping
Default
TC Snooping is disabled.
Views
System view
Predefined user roles
network-admin
Usage guidelines
TC Snooping and the spanning tree feature are mutually exclusive. You must globally disable the spanning tree feature before enabling TC Snooping.
Examples
# Globally disable the spanning tree feature and enable TC Snooping.
<Sysname> system-view
[Sysname] undo stp global enable
[Sysname] stp tc-snooping
Related commands
stp global enable
stp timer forward-delay
Use stp timer forward-delay to set the forward delay timer.
Use undo stp timer forward-delay to restore the default.
Syntax
stp [ vlan vlan-id-list ] timer forward-delay time
undo stp [ vlan vlan-id-list ] timer forward-delay
Default
The forward delay timer is 1500 centiseconds.
Views
System view
Predefined user roles
network-admin
Parameters
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. If you set the STP, RSTP, or MSTP forward delay, do not specify this option.
time: Specifies the forward delay in centiseconds, in the range of 400 to 3000 in increments of 100 (as in 400, 500, 600).
Usage guidelines
The forward delay timer determines the time interval of state transition. To prevent temporary loops, a spanning tree port goes through the learning (intermediate) state before it transits from the discarding state to the forwarding state. To stay synchronized with the remote device, the port has a wait period that is determined by the forward delay timer between transition states.
As a best practice, do not set the forward delay with this command. Instead, you can specify the network diameter of the switched network by using the stp bridge-diameter command. This command makes the spanning tree protocols automatically calculate the optimal settings for the forward delay timer. If the network diameter uses the default value, the forward delay timer also uses the default value.
Examples
# In MSTP mode, set the forward delay timer to 2000 centiseconds.
<Sysname> system-view
[Sysname] stp timer forward-delay 2000
# In PVST mode, set the forward delay timer for VLAN 2 to 2000 centiseconds.
<Sysname> system-view
[Sysname] stp vlan 2 timer forward-delay 2000
Related commands
stp bridge-diameter
stp timer hello
stp timer max-age
stp timer hello
Use stp timer hello to set the hello time.
Use undo stp timer hello to restore the default.
Syntax
stp [ vlan vlan-id-list ] timer hello time
undo stp [ vlan vlan-id-list ] timer hello
Default
The hello time is 200 centiseconds.
Views
System view
Predefined user roles
network-admin
Parameters
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. If you set the STP, RSTP, or MSTP hello time, do not specify this option.
time: Specifies the hello time in centiseconds, in the range of 100 to 1000 in increments of 100 (as in 100, 200, 300).
Usage guidelines
Hello time is the interval at which spanning tree devices send configuration BPDUs to maintain the spanning tree. If a device fails to receive configuration BPDUs within the set period of time, a new spanning tree calculation process is triggered.
As a best practice, do not set the hello time with this command. Instead, you can specify the network diameter of the switched network by using the stp bridge-diameter command. This command makes the spanning tree protocols automatically calculate the optimal settings for the hello timer. If the network diameter uses the default value, the hello timer also uses the default value.
Examples
# In MSTP mode, set the hello time to 400 centiseconds.
<Sysname> system-view
[Sysname] stp timer hello 400
# In PVST mode, set the hello time for VLAN 2 to 400 centiseconds.
<Sysname> system-view
[Sysname] stp vlan 2 timer hello 400
Related commands
stp bridge-diameter
stp timer forward-delay
stp timer max-age
stp timer max-age
Use stp timer max-age to set the max age timer.
Use undo stp timer max-age to restore the default.
Syntax
stp [ vlan vlan-id-list ] timer max-age time
undo stp [ vlan vlan-id-list ] timer max-age
Default
The max age is 2000 centiseconds.
Views
System view
Predefined user roles
network-admin
Parameters
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. If you set the STP, RSTP, or MSTP max age, do not specify this option.
time: Specifies the max age in centiseconds, in the range of 600 to 4000 in increments of 100 (as in 600, 700, 800).
Usage guidelines
In the CIST of an MSTP network, the device determines whether a configuration BPDU received on a port has expired based on the max age timer. If the configuration BPDU has expired, a new spanning tree calculation process starts. The max age timer takes effect only on the CIST (or MSTI 0).
As a best practice, do not set the max age timer with this command. Instead, you can specify the network diameter of the switched network by using the stp bridge-diameter command. This command makes the spanning tree protocols automatically calculate the optimal settings for the max age timer. If the network diameter uses the default value, the max age timer also uses the default value.
Examples
# In MSTP mode, set the max age timer to 1000 centiseconds.
<Sysname> system-view
[Sysname] stp timer max-age 1000
# In PVST mode, set the max age timer for VLAN 2 to 1000 centiseconds.
<Sysname> system-view
[Sysname] stp vlan 2 timer max-age 1000
Related commands
stp bridge-diameter
stp timer forward-delay
stp timer hello
stp timer-factor
Use stp timer-factor to configure the timeout period by setting the timeout factor.
Timeout period = timeout factor × 3 × hello time.
Use undo stp timer-factor to restore the default.
Syntax
stp timer-factor factor
undo stp timer-factor
Default
The timeout factor of the device is set to 3.
Views
System view
Predefined user roles
network-admin
Parameters
factor: Specifies the timeout factor in the range of 1 to 20.
Usage guidelines
In a stable network, each non-root-bridge forwards configuration BPDUs to surrounding devices at the interval of hello time to determine whether any link fails. If a device does not receive a BPDU from the upstream device within nine times of the hello time, it assumes that the upstream device has failed. Then it will start a new spanning tree calculation process.
As a best practice, set the timeout factor to 5, 6, or 7 in the following situations:
· To prevent undesired spanning tree calculations. An upstream device might be too busy to forward configuration BPDUs in time, for example, many Layer 2 interfaces are configured on the upstream device. In this case, the downstream device fails to receive a BPDU within the timeout period and then starts an undesired spanning tree calculation.
· To save network resources on a stable network.
Examples
# Set the timeout factor of the device to 7.
<Sysname> system-view
[Sysname] stp timer-factor 7
Related commands
stp timer hello
stp transmit-limit
Use stp transmit-limit to set the BPDU transmission rate of a port.
Use undo stp transmit-limit to restore the default.
Syntax
stp transmit-limit limit
undo stp transmit-limit
Default
The BPDU transmission rate of all ports is 10.
Views
Layer 2 Ethernet interface view
Layer 2 aggregate interface view
Predefined user roles
network-admin
Parameters
limit: Specifies the BPDU transmission rate in the range of 1 to 255.
Usage guidelines
The maximum number of BPDUs a port can send within each hello time equals the BPDU transmission rate plus the hello timer value.
A larger BPDU transmission rate value requires more system resources. An appropriate BPDU transmission rate setting can prevent spanning tree protocols from using excessive bandwidth resources during network topology changes. As a best practice, use the default value.
If this command is configured in Layer 2 Ethernet interface view, it takes effect only on that interface.
If this command is configured in Layer 2 aggregate interface view, it takes effect only on the aggregate interface.
If this command is configured on a member port in an aggregation group, it takes effect only after the port leaves the aggregation group.
Examples
# Set the BPDU transmission rate of GigabitEthernet 1/0/1 to 5.
<Sysname> system-view
[Sysname] interface gigabitethernet 1/0/1
[Sysname-GigabitEthernet1/0/1] stp transmit-limit 5
stp vlan enable
Use stp vlan enable to enable the spanning tree feature for VLANs.
Use undo stp enable to disable the spanning tree feature for VLANs.
Syntax
stp vlan vlan-id-list enable
undo stp vlan vlan-id-list enable
Default
The spanning tree feature is enabled in VLANs.
Views
System view
Predefined user roles
network-admin
Parameters
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.
Usage guidelines
When you enable the spanning tree feature, the device operates in STP, RSTP, PVST, or MSTP mode, depending on the spanning tree mode setting.
When you enable the spanning tree feature, the device dynamically maintains the spanning tree status of VLANs, based on received configuration BPDUs. When you disable the spanning tree feature, the device stops maintaining the spanning tree status.
Examples
# In PVST mode, globally enable the spanning tree feature and then enable the spanning tree feature for VLAN 2.
<Sysname> system-view
[Sysname] stp mode pvst
[Sysname] stp global enable
[Sysname] stp vlan 2 enable
Related commands
stp enable
stp global enable
stp mode
vlan-mapping modulo
Use vlan-mapping modulo to map VLANs in an MST region to MSTIs according to the specified modulo value and quickly create a VLAN-to-instance mapping table.
Syntax
vlan-mapping modulo modulo
Default
All VLANs are mapped to the CIST (MSTI 0).
Views
MST region view
Predefined user roles
network-admin
Parameters
modulo: Specifies the modulo value. The value range for this argument is 1 to 64.
Usage guidelines
You cannot map a VLAN to different MSTIs. If you map a VLAN that has been mapped to an MSTI to a new MSTI, the old mapping is automatically deleted.
This command maps each VLAN to the MSTI with ID (VLAN ID – 1) % modulo + 1. (VLAN ID – 1) % modulo is the modulo operation for (VLAN ID – 1). If the modulo value is 15, then VLAN 1 is mapped to MSTI 1, VLAN 2 to MSTI 2, …, VLAN 15 to MSTI 15, VLAN 16 to MSTI 16, and so on.
Examples
# Map VLANs to MSTIs as per modulo 8.
<Sysname> system-view
[Sysname] stp region-configuration
[Sysname-mst-region] vlan-mapping modulo 8
Related commands
active region-configuration
check region-configuration
display stp region-configuration
region-name
revision-level