200-301 Question 213
Single answerYou are configuring a network that uses Rapid PVST+ Spanning Tree Protocol (STP). During troubleshooting, you notice that a port on a switch transitions directly to the forwarding state, bypassing the listening and learning states. What could be the reason for this behavior?
- A
The port is configured as an edge port using PortFast.
- B
The port is experiencing a BPDU guard violation.
- C
The port is a designated port for the VLAN.
- D
The port is configured as a root port.
Show answer and explanation
Correct answer: A
Explanation
In Rapid PVST+, the PortFast feature is used to configure edge ports, which are ports connected directly to end devices (rather than other switches). Edge ports bypass the listening and learning states and transition immediately to the forwarding state to reduce convergence time. This behavior is specific to ports configured with PortFast and is not observed on root or designated ports unless explicitly configured.
- A. Correct.
This is the correct answer. In Rapid PVST+, enabling PortFast on a port configures it as an edge port, allowing it to bypass the listening and learning states and move directly to the forwarding state.
- B. Incorrect.
This is incorrect. A BPDU guard violation causes the port to be placed in an error-disabled state, not to bypass the listening and learning states.
- C. Incorrect.
This is incorrect. A designated port forwards traffic but still transitions through the listening and learning states unless configured otherwise.
- D. Incorrect.
This is incorrect. A root port is the interface with the best path to the root bridge and also transitions through the normal STP states unless configured with PortFast.