A network engineer configured an Ethernet switch using these commands.
Switchone (config) # Spanning-tree portfast bpdufilter default.
Which statement about the spanning-tree portfast feature on the switch is true?
A . If an interface is enabled for portfast receives BDPU, the port goes through the spanning-tree listening, learning, and forwarding states.
B . If an interface is enabled for portfast receives BDPU, the port does not go through the spanning-tree listening, learning, and forwarding states.
C . If an interface is enabled for portfast receives BDPU, the port is shut down immediately.
D . If an interface is enabled for portfast receives BDPU, the port goes into the spanning-tree inconsistent state.
Answer: A
Explanation:
STP PortFast causes a Layer 2 LAN interface configured as an access port to enter the forwarding state immediately, bypassing the listening and learning states.
However, the "Spanning-tree portfast bpdufilter default" command specifies that if a BPDU is received on that port, then the default action of STP of listening, learning, and forwarding states should be used.
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