HP Cisco MDS 9120 Cisco Nexus 5000 Series Command Reference Release 4.0(1a)N2( - Page 197

Chapter 2 Ethernet Commands spanning-tree bpduguard Send comments to [email protected] spanning-tree bpduguard 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 enable disable Enables BPDU Guard on this interface. Disables BPDU Guard on this interface. Command Default The setting that is already configured when you enter the spanning-tree port type edge bpduguard default command. Command Modes Interface configuration mode Command History Release 4.0(0)N1(1a) Modification This command was introduced. Usage Guidelines BPDU Guard prevents a port from receiving BPDUs. If the port still receives a BPDU, it is put in the error-disabled state as a protective measure. Caution Be careful when using this command. You should use this command only with interfaces that connect to end stations; otherwise, an accidental topology loop could cause a data-packet loop and disrupt the switch and network operation. When you enable this BPDU Guard command globally, the command applies only to spanning tree edge ports. See spanning-tree port type edge bpduguard default for more information on the global command for BPDU Guard. However, when you enable this feature on an interface, it applies to that interface regardless of the spanning tree port type. This command has three states: • spanning-tree bpduguard enable-Unconditionally enables BPDU Guard on the interface. • spanning-tree bpduguard disable-Unconditionally disables BPDU Guard on the interface. • no spanning-tree bpduguard-Enables BPDU Guard on the interface if it is an operational spanning tree edge port and if the spanning-tree port type edge bpduguard default command is configured. Typically, this feature is used in a service-provider environment where the network administrator wants to prevent an access port from participating in the spanning tree. OL-16599-01 Cisco Nexus 5000 Series Command Reference 2-49