Command Line Interface Guide

756 Spanning Tree Commands
Default Configuration
The default cost is 0, which signifies that the cost is automatically calculated
based on port speed.
• 10G Port path cost — 2000
•
Port Channel — 20,000
•
1000 mbps (giga) — 20,000
•
100 mbps — 200,000
•
10 mbps — 2,000,000
Command Mode
Interface Configuration (gigabitethernet, port-channel, tengigabitethernet,
fortygigabitethernet) mode
User Guidelines
This command configures the external cost. Since by default each switch is in
its own region, the external cost is considered in determining the spanning
tree of the network.
This command is also used to configure the rstp path cost.
Example
The following example configures the spanning-tree cost on 1/0/5 to 35000.
console(config)#interface gigabitethernet 1/0/5
console(config-if-1/0/5)#spanning-tree cost 35000
spanning-tree disable
Use the spanning-tree disable command in Interface Configuration mode to
disable spanning-tree on a specific port. To enable spanning-tree on a port,
use the no form of this command.
Syntax
spanning-tree disable
no spanning-tree disable
2CSPC4.X8100-SWUM100.book Page 756 Wednesday, August 29, 2012 6:23 PM