Quick Reference Guide

Spanning-Tree Commands 377
DELL CONFIDENTIAL – PRELIMINARY 5/15/12 – FOR PROOF ONLY
User Guidelines
There are no user guidelines for this command.
Example
The following example configures the spanning priority on Ethernet port 1/e15 to 96.
spanning-tree portfast
The spanning-tree portfast Interface Configuration mode command enables PortFast mode. In
PortFast mode, the interface is immediately put into the forwarding state upon linkup without
waiting for the standard forward time delay. Use the no form of this command to disable PortFast
mode.
Syntax
• spanning-tree portfast [auto]
• no spanning-tree portfast
• auto — Specifies that the software waits for 3 seconds (With no BPDUs received on the
interface) before putting the interface into the PortFast mode.
Default Configuration
PortFast mode is disabled.
Command Mode
Interface Configuration (Ethernet, port-channel) mode.
User Guidelines
• This feature should be used only with interfaces connected to end stations. Otherwise, an
accidental topology loop could cause a data packet loop and disrupt device and network
operations.
Example
The following example enables PortFast on Ethernet port 1/e15.
Console(config)# interface ethernet 1/e15
Console(config-if)# spanning-tree port-priority 96
Console(config)# interface ethernet 1/e15
Console(config-if)# spanning-tree portfast