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| 3.7 |  | Tuning, Verifying, and Troubleshooting Spanning-Tree Protocol |
| 3.7.1 |  | Configuring PortFast |

A port with the PortFast feature enabled is moved directly to the spanning tree Forwarding state without waiting for the standard forward-time delay.

Use PortFast only when connecting a single end station to an access or trunk port. Enabling this feature on a port connected to a switch or hub could prevent spanning tree from detecting and disabling loops in the network, which could cause broadcast storms and address-learning problems.

When the voice VLAN feature is enabled, the PortFast feature is automatically enabled. When voice VLAN is disabled, the PortFast feature is not automatically disabled.

Enable this feature if the switch is running PVST or MSTP. The MSTP is available only if the EI is installed on the switch.

Beginning in privileged EXEC mode, follow the steps outlined in Figure to enable PortFast.

Use the spanning-tree portfast global configuration command to globally enable the PortFast feature on all non-trunking ports.

To disable the PortFast feature, use the no spanning-tree portfast interface configuration command.