Topology Change and Topology Change Detection
Set Spanning Tree Compatibility to STP
Restore Spanning Tree Compatibility
Restore the Default Bridge Priority
Configuring the STP Port Priority
Port Priority Configuration Topology Example
Restore the Default Port Priority
Configuring the Spanning Tree Link Type
Spanning Tree Link Type Overview
Configure the Interface Link Type
Restore the Default Interface Link Type
Configuring the Spanning Tree Portfast Port
Spanning Tree Portfast Port Overview
Restore the Default Portfast Port
Configuring Spanning Tree Timers
Restore the Default Timer Values
Configuring the Pseudo Root ID
Display Spanning Tree Information for Active Ports
Display Detailed Spanning Tree Information
Display the Spanning Tree Port-Specification Configuration
Display a Summary of the Spanning Tree Information for the Configuration
Specify MST Forward Time, Hello Time, and Max Age
Set the Spanning Tree Operating Mode
Specify MST Mode Configurations
Configuring the Spanning Tree Switch Priority
Configure the Spanning Tree Switch Priority
Restore the Default Spanning Tree Priority
Configure MST Properties of an Interface
Restore the Default MSTP Priority
Configuring the Interval Between Generation of Configuration Messages
Configure the MST Interval Between Generation of Configuration Messages
Restore the Default Interval Between Generation of Configuration Messages
Configuring the Maximum Hop Count
Configure the Maximum Hop Count
Restore the Default Maximum Hop Count
Configuring the Pseudo Root ID
Configuring Features Common to RSTP and MSTP
Clear Spanning Tree MSTP Counters
Configuring the Transit Hold Count
Configure the Transmit Hold Count
Restore the Default Transmit Hold Count Value
Configuring the Dynamic Path Cost
Dynamic Path Cost Topology Example
Configure the Dynamic Path Cost
Configure the Dynamic Path Cost in an Aggregate Port
Disable the Dynamic Path Cost Calculation
Configure the Dynamic Path Cost Lag Speed in an Aggregate Port
Disable the Dynamic Path Cost Lag Speed Calculation
Enable Spanning Tree Loop Guard
Show Spanning Tree Performance Data
Configuring Automatic Detection of Edge Devices or Bridges
Configure Automatic Detection of Edge Devices or Bridges
Disable Automatic Detection of Edge Devices or Bridges
Configuring the Restricted Role
Configuring the Topology Change
Restart the Protocol Migration Process
Configuring the Spanning Tree BPDU Receive Status
Configure the Spanning Tree BPDU Receive Status
Disable the Spanning Tree BPDU Receive Status
Configuring the Spanning Tree BPDU Transmit Status
Configure the Spanning Tree BPDU Transmit Status
Disable the Spanning Tree BPDU Transmit Status
Configuring the Spanning Tree L2GP Status
Configure the Spanning Tree L2GP Status
Display the Spanning Port Information
Display the MST Configuration and Status
Topology After Configuring the Bridge Priority and Port Path Cost in RSTP
See RSTP Configuration Guidelines for the topology setup. By default, all the switches run MSTP.
SEFOS# configure terminal SEFOS(config)# spanning-tree mode rstp SEFOS(config)# end
SEFOS# configure terminal SEFOS(config)# spanning-tree mode rstp SEFOS(config)# spanning-tree priority 0 SEFOS(config)# end
Note - Switch 3 is now the root of the spanning tree because the bridge priority is lesser than the other bridges on the spanning tree.
SEFOS# show spanning-tree Root Id Priority 0 Address 00:03:02:03:04:01 Cost 200000 Port Ex0/2 Hello Time 2 Sec, Max Age 20 Sec, Forward Delay 15 Sec Bridge is executing the rstp compatible Spanning Tree Protocol Bridge Id Priority 32768 Address 00:01:02:03:04:01 Hello Time 2 sec, Max Age 20 sec, Forward Delay 15 sec Name Role State Cost Prio Type ---- ---- ----- ---- ---- ------ Ex0/1 Designated Forwarding 200000 128 SharedLan Ex0/2 Root Forwarding 200000 128 SharedLan
SEFOS# show spanning-tree Root Id Priority 0 Address 00:03:02:03:04:01 Cost 200000 Port Ex0/2 Hello Time 2 Sec, Max Age 20 Sec, Forward Delay 15 Sec Bridge is executing the rstp compatible Spanning Tree Protocol Bridge Id Priority 32768 Address 00:02:02:03:04:01 Hello Time 2 sec, Max Age 20 sec, Forward Delay 15 sec Name Role State Cost Prio Type ---- ---- ----- ---- ---- ------ Ex0/1 Alternate Discarding 200000 128 SharedLan Ex0/2 Root Forwarding 200000 128 SharedLan
SEFOS# show spanning-tree We are the root of the Spanning Tree Root Id Priority 0 Address 00:03:02:03:04:01 Cost 0 Port 0 Hello Time 2 Sec, Max Age 20 Sec, Forward Delay 15 Sec Bridge is executing the rstp compatible Spanning Tree Protocol Bridge Id Priority 0 Address 00:03:02:03:04:01 Hello Time 2 sec, Max Age 20 sec, Forward Delay 15 sec Name Role State Cost Prio Type ---- ---- ----- ---- ---- ------ Ex0/1 Designated Forwarding 200000 128 SharedLan Ex0/2 Designated Forwarding 200000 128 SharedLan
SEFOS# configure terminal SEFOS(config)# interface extreme-ethernet 0/2 SEFOS(config-if)# spanning-tree cost 4094 SEFOS(config-if)# end
Note - This command configures port P1 of switch 2 as designated and port P1 of switch 1 as alternate.
SEFOS# show spanning-tree Root Id Priority 0 Address 00:03:02:03:04:01 Cost 200000 Port Ex0/2 Hello Time 2 Sec, Max Age 20 Sec, Forward Delay 15 SecBridge is executing the rstp compatible Spanning Tree ProtocolBridge Id Priority 32768 Address 00:01:02:03:04:01 Hello Time 2 sec, Max Age 20 sec, Forward Delay 15 sec Name Role State Cost Prio Type ---- ---- ----- ---- ---- ------Ex0/1 Alternate Discarding 200000 128 SharedLanEx0/2 Root Forwarding 200000 128 SharedLan
SEFOS# show spanning-tree Root Id Priority 0 Address 00:03:02:03:04:01 Cost 4094 Port Ex0/2 Hello Time 2 Sec, Max Age 20 Sec, Forward Delay 15 Sec Bridge is executing the rstp compatible Spanning Tree Protocol Bridge Id Priority 32768 Address 00:02:02:03:04:01 Hello Time 2 sec, Max Age 20 sec, Forward Delay 15 sec Name Role State Cost Prio Type ---- ---- ----- ---- ---- ------ Ex0/1 Designated Forwarding 200000 128 SharedLan Ex0/2 Root Forwarding 4094 128 SharedLan
SEFOS# show spanning-tree We are the root of the Spanning Tree Root Id Priority 0 Address 00:03:02:03:04:01 Cost 0 Port 0 Hello Time 2 Sec, Max Age 20 Sec, Forward Delay 15 Sec Bridge is executing the rstp compatible Spanning Tree Protocol Bridge Id Priority 0 Address 00:03:02:03:04:01 Hello Time 2 sec, Max Age 20 sec, Forward Delay 15 sec Name Role State Cost Prio Type ---- ---- ----- ---- ---- ------ Ex0/1 Designated Forwarding 200000 128 SharedLan Ex0/2 Designated Forwarding 200000 128 SharedLan