Users Guide

Layer 2 Switching Commands 821
User Guidelines
This command only applies to access ports. The command is to be used only
with interfaces connected to end stations. Otherwise, an accidental topology
loop could cause a data packet loop and disrupt switch and network
operations.
An interface with portfast mode enabled is moved directly to the spanning
tree forwarding state when linkup occurs without waiting the standard
forward-time delay.
Example
The following example enables portfast on Gi1/0/5.
console(config)#interface gigabitethernet 1/0/5
console(config-if-Gi1/0/5)#spanning-tree portfast
spanning-tree portfast bpdufilter default
The spanning-tree portfast bpdufilter default command disables the
transmission and reception of BPDUs on portfast enabled ports. Use the “no”
form of the command to enable the transmission and receipt of BPDUs.
Syntax
spanning-tree portfast bpdufilter default
no spanning-tree portfast bpdufilter default
Default Configuration
This feature is disabled by default.
Command Mode
Global Configuration mode, Interface Configuration mode (physical
interface and port-channels)
User Guidelines
BPDU filtering disables both the sending and receiving of BPDUs on portfast
enabled ports.