Users Guide

Layer 2 Switching Commands 820
Command Mode
Global Configuration mode
User Guidelines
The priority value must be a multiple of 4096. The priority will be set to the
nearest multiple of 4096 if not an exact multiple of 4096.
Bridge priority configuration is given preference over the root
primary/secondary configuration. Root primary/secondary configuration is
given preference over the DRC configuration.
The switch with the lowest priority is selected as the root of the spanning tree.
Example
The following example configures the spanning tree priority of instance 1 to
4096.
console(config)#spanning-tree mst 1 priority 4096
spanning-tree portfast
Use the spanning-tree portfast command in Interface Configuration mode to
enable portfast mode. In portfast mode, the interface is immediately put into
the forwarding state upon linkup, without waiting for the timer to expire. To
disable portfast mode, use the no form of this command.
Syntax
spanning-tree portfast
no spanning-tree portfast
Default Configuration
Portfast mode is disabled.
Command Mode
Interface Configuration (gigabitethernet, port-channel, tengigabitethernet,
fortygigabitethernet) mode