Spanning Tree Commands 4

spanning-tree portfast

This command sets an interface to fast forwarding. Use the no form to disable fast forwarding.

Syntax

[no] spanning-tree portfast

Default Setting

Disabled

Command Mode

Interface Configuration (Ethernet, Port Channel)

Command Usage

This command is used to enable/disable the fast spanning-tree mode for the selected port. In this mode, ports skip the Discarding and Learning states, and proceed straight to Forwarding.

Since end-nodes cannot cause forwarding loops, they can be passed through the spanning tree state changes more quickly than allowed by standard convergence time. Fast forwarding can achieve quicker convergence for end-node workstations and servers, and also overcome other STA related timeout problems. (Remember that fast forwarding should only be enabled for ports connected to a LAN segment that is at the end of a bridged LAN or for an end-node device.)

This command is the same as spanning-treeedge-port, and is only included for backward compatibility with earlier products. Note that this command may be removed for future software versions.

Example

Console(config)#interface ethernet 1/5

Console(config-if)#spanning-tree portfast

Console(config-if)#

Related Commands

spanning-treeedge-port(4-140)

spanning-tree link-type

This command configures the link type for Rapid Spanning Tree. Use the no form to restore the default.

Syntax

spanning-tree link-type {auto point-to-point shared} no spanning-tree link-type

auto - Automatically derived from the duplex mode setting.

point-to-point- Point-to-point link.

shared - Shared medium.

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SMC Networks 16 10BASE-T Spanning-tree portfast, Spanning-tree link-type, Syntax No spanning-tree portfast Default Setting