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 bpduguard
spanning-tree bpd uguard
To enable BPDU guard on an interface, use the spanning-tree bpduguard command. To return to the
default settings, use the no form of this command.
spanning-tree bpduguard {enable | disable}
no spanning-tree bpduguard
Syntax Description
Defaults BPDU guard is disable d.
Command Modes Interface configur ation mode
Command History
Usage Guidelines BPDU guard is a feature that prevents a port from receiving BPDUs. This feature is typically used in a
service provider environment where the administrator wants to prevent an access port from participating
in the spanning tree. If the port still receives a BPDU, it is put in the ErrDisable state as a protective
measure. This command has three states:
• spanning-tree bpduguard enable—This state unconditionally enables BPDU guard on the
interface.
• spanning-tree bpduguard disable—This state unconditionally disables BPDU guard on the
interface.
• no spanning-tree bpduguard—This state enables BPDU guard on the interface if it is in the
operational PortFast state and if the spanning-tree portfast bpduguard default command is
configured.
Examples This example shows how to enable BPDU guard on this interface:
Switch(config-if)# spanning-tree bpduguard enable
Switch(config-if)#
Related Commands
enable Enables BPDU guard on this interface.
disable Disables BPDU guard on this interface.
Release Modification
12.1(12c)EW Support f or this command was introduc ed on the Catalyst 4500 ser ies switch.
Command Description
show spanning-tree Displays spanning-tree information.
spanning-tree portfast bpdufilter
default
Enables the BPDU filtering by default on all PortFast ports.