350-401 Question 142

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• 1

  the port has been connected to an unauthorized device or misconfigured. To resolve the error, BPDU Guard needs to be disabled on the interface and the interface needs to be brought out of the err-disable state. Option C is the correct set of commands to resolve this error as it enables BPDU Guard on the interface, which will prevent any unauthorized BPDU frames from being received on the interface, and then the interface is shut down and then brought back up. Option B is not the correct set of commands to resolve the error. This is because the "no" keyword is used with the "spanning-tree bpduguard enable" command, which would disable BPDU Guard on the interface. Instead, the "spanning-tree bpduguard enable" command needs to be omitted, and the "spanning-tree portfast disable" command needs to be used to prevent BPDU Guard from being triggered again on this interface

• 1

  sw2#show interfaces status | i /3|Stat Port Name Status Vlan Duplex Speed Type Et0/3 connected trunk auto auto unknown sw2#

• Chose B2

  tested: sw2(config-if)#spanning-tree bpduguard enable sw2(config-if)# *Dec 17 17:23:04.850: %SPANTREE-2-BLOCK_BPDUGUARD: Received BPDU on port Et0/3 with BPDU Guard enabled. Disabling port. sw2(config-if)# *Dec 17 17:23:04.850: %PM-4-ERR_DISABLE: bpduguard error detected on Et0/3, putting Et0/3 in err-disable state *Dec 17 17:23:05.850: %LINEPROTO-5-UPDOWN: Line protocol on Interface Ethernet0/3, changed state to down sw2(config-if)# *Dec 17 17:23:06.853: %LINK-3-UPDOWN: Interface Ethernet0/3, changed state to down sw2(config-if)# sw2#show interfaces status | i /3|Stat Port Name Status Vlan Duplex Speed Type Et0/3 err-disabled 1 auto auto unknown sw2#