Administrator Guide

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
Removing an Interface from the
Spanning Tree Group
To remove a Layer 2 interface from the spanning tree topology, use the following command.
• Disable spanning tree on a Layer 2 interface.
INTERFACE mode
no 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 Networking recommends that only experienced network administrators change the spanning
tree parameters. Poorly planned modification of the spanning tree parameters can negatively affect
network performance.
The following table displays the default values for STP.
Table 66. STP Default Values
STP Parameters Default Value
Forward Delay 15 seconds
Hello Time 2 seconds
Max Age 20 seconds
Port Cost
• 40-Gigabit Ethernet interfaces
• 10-Gigabit Ethernet interfaces
• 1
• 2
• 1
Spanning Tree Protocol (STP) 875