300-415 Question 156
Single answerYou are configuring EIGRP on a Cisco SD-WAN deployment to ensure dynamic routing between branch sites. During the configuration, you notice that EIGRP routes are not being advertised between the vEdge routers. What could be the most likely reason for this issue?
- A
EIGRP is not supported on vEdge routers in Cisco SD-WAN.
- B
The EIGRP process has not been configured under the VPN routing instance.
- C
The correct EIGRP Autonomous System (AS) number has not been configured on both vEdge routers.
- D
The EIGRP routes are being blocked by a centralized control policy.
Show answer and explanation
Correct answer: B
Explanation
In Cisco SD-WAN, EIGRP requires configuration within the appropriate VPN routing instance on vEdge routers to function correctly. If the EIGRP process is not configured within the VPN, routes will not be advertised, even if other parameters like AS number are correctly set. This is a common oversight during deployment.
- A. Incorrect.
EIGRP is supported on vEdge routers in Cisco SD-WAN when configured under the appropriate VPN. This is not the correct answer.
- B. Correct.
EIGRP must be explicitly configured under the corresponding VPN routing instance on the vEdge routers. Failure to do so will prevent EIGRP routes from being advertised. This is the correct answer.
- C. Incorrect.
While the AS number must match for EIGRP peers to form an adjacency, this issue would prevent adjacencies, not necessarily route advertisement. This is not the most likely cause in this scenario.
- D. Incorrect.
Centralized control policies can manipulate routing behavior, but they are not a default configuration. It is unlikely that a centralized control policy is the cause unless explicitly configured.