Which result occurs when PortFast is enabled on an interface that is connected to another switch?
A . Spanning tree may fail to detect a switching loop in the network that causes broadcast storms
B . VTP is allowed to propagate VLAN configuration information from switch to switch automatically
C . Root port choice and spanning tree recalculation are accelerated when a switch link goes down
D . After spanning tree converges PortFast shuts down any port that receives BPDUS
Answer: A
Explanation:
Enabling the PortFast feature causes a switch or a trunk port to enter the STP forwarding-state immediately or upon a linkup event, thus bypassing the listening and learning states. Note: To enable portfast on a trunk port you need the trunk keyword “spanning-tree portfast trunk”