300-415 Question 145
Single answerA retail company is deploying Cisco SD-WAN across its branch locations. To ensure high availability for the LAN side of the branch network, the company plans to implement VRRP on its SD-WAN Edge devices. During testing, you observe that traffic does not fail over when the primary VRRP device fails. What could be the cause of this issue?
- A
The same VRRP group ID is not configured on both SD-WAN Edge devices.
- B
The VRRP priority value on the secondary device is higher than the primary device.
- C
The VRRP advertisements are not being sent over the LAN interface due to incorrect interface configuration.
- D
The feature template applied to the SD-WAN Edge devices does not support VRRP.
Show answer and explanation
Correct answer: C
Explanation
For VRRP to function properly, the devices must exchange advertisements over the configured LAN interface. If advertisements are not sent or received, the secondary device will not detect the primary device's failure, preventing failover. Therefore, verifying the interface configuration and ensuring VRRP advertisements are being properly sent and received is critical in resolving this issue.
- A. Incorrect.
The VRRP group ID must be the same on both devices for proper operation, but this is not the issue in this scenario since lack of failover typically points to interface or advertisement problems.
- B. Incorrect.
The priority value of the secondary device being higher than the primary device would result in the secondary device becoming the master. However, this does not explain a lack of failover when the primary fails.
- C. Correct.
If VRRP advertisements are not being sent over the LAN interface due to incorrect configuration, the secondary device will not detect the failure of the primary device, preventing failover.
- D. Incorrect.
Cisco SD-WAN feature templates support VRRP, so this is not the root cause of the issue.