Specifications

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Catalyst 4500 Se ries S wit ch C is co IO S C om mand R efer ence —Re lease I OS XE 3 .3.0 XO(1 5.1 (1)XO)
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Chapter 2 Cisco IOS Commands for the Catalyst 4500 Series Switches
spanning-tree portfast bpduguard default
spanning-tree port fast bpduguard default
To enable BPDU guard by default on all the PortFast ports, use the spanning-tree portfast bpduguard
default command. To return to the default settings, use the no form of this command.
spanning-tree portfast bpduguard default
no spanning-tree portfast bpduguard default
Syntax Description This command has no keywords or arguments.
Defaults BPDU guard is disable d.
Command Modes Global configura tion mode
Usage Guidelines
Caution Use this command only with the interfaces that connect to the end stations; otherwise, an accidental
topology loop could cause a data pac ket loop and disrupt the Cataly st 4500 series switch and network
operation.
BPDU guard disables a por t if it re ceives a BPDU . BPDU guar d is applie d only on port s that are PortFast
enabled and are in an operational Port Fast state.
Examples This example shows how to enable BPDU guard by defaul t:
Switch(config)# spanning-tree portfast bpduguard default
Switch(config)#
Related Commands Command Description
show spanning-tree mst Displays MST protocol informatio n.
spanning-tree bpduguard Enables BPDU guard on an interface.