300-440 Question 43
Select 2An enterprise network administrator is troubleshooting a routing issue between two devices connected over a high-speed link. They decide to implement Bidirectional Forwarding Detection (BFD) to quickly detect failures in the forwarding path. What must the administrator consider when configuring BFD in this scenario?
- A
BFD operates independently of routing protocols and does not require integration with them.
- B
BFD can only operate in asynchronous mode to detect link failures.
- C
BFD requires that both devices on either end of the link support and enable it for successful operation.
- D
BFD can provide sub-second failure detection for fast convergence of routing protocols.
- E
BFD requires manual configuration of timers and intervals for optimal performance.
Show answer and explanation
Correct answers: C, D
Explanation
BFD is a lightweight protocol used to detect link or forwarding path failures quickly, which is essential for fast routing protocol convergence. It requires both ends of the link to support and enable BFD to function. Additionally, its ability to provide sub-second failure detection is a key benefit, making it a critical tool for enterprise networks with stringent uptime requirements. While manual configuration of timers can enhance performance, it is not required in all scenarios, and default values can often suffice.
- A. Incorrect.
BFD is designed to work with routing protocols by providing fast failure detection. It is not independent of routing protocols; rather, it enhances their operation by reducing failure detection time.
- B. Incorrect.
BFD can operate in two modes: asynchronous and demand. It is not limited to asynchronous mode.
- C. Correct.
BFD requires both devices on either end of the link to support and enable BFD for it to function. If one device does not support BFD, it cannot be used.
- D. Correct.
BFD is designed for sub-second failure detection, enabling faster convergence of routing protocols by notifying them of link failures promptly.
- E. Incorrect.
While BFD allows for manual configuration of timers and intervals, it also supports default values. However, optimal performance often requires manual tuning depending on the network environment.