Setup Guide

To verify that STP is enabled, use the show config command from PROTOCOL SPANNING TREE mode.
DellEMC(conf)#protocol spanning-tree 0
DellEMC(config-span)#show config
!
protocol spanning-tree 0
no disable
DellEMC#
To view the spanning tree conguration and the interfaces that are participating in STP, use the show spanning-tree 0 command
from EXEC privilege mode. If a physical interface is part of a port channel, only the port channel is listed in the command output.
To conrm that a port is participating in Spanning Tree, use the show spanning-tree 0 brief command from EXEC privilege mode.
Adding an Interface to the Spanning Tree Group
To add a Layer 2 interface to the spanning tree topology, use the following command.
• Enable spanning tree on a Layer 2 interface.
INTERFACE mode
spanning-tree 0
Modifying Global Parameters
You can modify the spanning tree parameters. The root bridge sets the values for forward-delay, hello-time, and max-age and overwrites
the values set on other bridges participating in STP.
NOTE
: Dell EMC Networking recommends that only experienced network administrators change the spanning tree parameters.
Poorly planned modication of the spanning tree parameters can negatively aect network performance.
The following table displays the default values for STP.
Table 128. STP Default Values
STP Parameters Default Value
Forward Delay 15 seconds
Hello Time 2 seconds
Max Age 20 seconds
Port Cost
• 100-Mb/s Ethernet interfaces
• 1-Gigabit Ethernet interfaces
• 10-Gigabit Ethernet interfaces
• 40-Gigabit Ethernet interfaces
• Port Channel with 100 Mb/s Ethernet interfaces
• Port Channel with 1-Gigabit Ethernet interfaces
• Port Channel with 10-Gigabit Ethernet interfaces
• Port Channel with 40-Gigabit Ethernet interfaces
• 200000
• 20000
• 2000
• 1400
• 180000
• 18000
• 1800
• 600
Port Priority 8
• Change the forward-delay parameter (the wait time before the interface enters the Forwarding state).
PROTOCOL SPANNING TREE mode
forward-delay seconds
Spanning Tree Protocol (STP)
865