Users Guide

Table Of Contents
Layer 2 Switching Commands 832
Default Configuration
Auto portfast mode is enabled by default.
Command Mode
Interface Configuration (Ethernet, Port Channel) mode
User Guidelines
There are no user guidelines for this command.
Example
The following example enables spanning-tree functionality on Gigabit
ethernet interface 4/0/1.
console#config
console(config)#interface gigabitethernet 4/0/1
console(config-if-4/0/1)#spanning-tree auto-portfast
spanning-tree backbonefast
Use the spanning-tree backbonefast command to enable the detection of
indirect link failures and accelerate spanning tree convergence on
STP-PV/RSTP-PV configured switches using Indirect Link Rapid
Convergence (IRC). IRC accelerates finding an alternative path when an
indirect link to the root port goes down. Use the no form of the command to
disable the IRC feature.
Syntax
spanning-tree backbonefast
no spanning-tree backbonefast
Default Configuration
This command has no default configuration.
Command Modes
Global Configuration Mode