Cisco 200-125 Exam
Which Cisco Catalyst feature automatically disables the port in an operational PortFast upon receipt of a BPDU?
- A. BackboneFast
- B. UplinkFast
- C. Root Guard
- D. BPDU Guard
- E. BPDU Filter
Answer: Option D.
Explanation:
We only enable PortFast feature on access ports (ports connected to end stations). But if someone does not know he can accidentally plug that port to another switch and a loop may occur when BPDUs are being transmitted and received on these ports. With BPDU Guard, when a PortFast receives a BPDU, it will be shut down to prevent a loop.