350-401 Question 98
Single answerA network engineer is tasked with deploying Virtual Routing and Forwarding (VRF) on a Cisco router to segment traffic between two departments: Finance and HR. The engineer has configured the VRFs and assigned interfaces to the respective VRFs. However, no communication is occurring between the two departments even though static routes have been configured in each VRF. What is the most likely reason for this issue?
- A
The static routes are incorrectly configured.
- B
VRF Lite does not support communication between VRFs.
- C
A route target is required to enable communication between VRFs.
- D
VRF-aware routing protocols must be configured to establish inter-VRF communication.
Show answer and explanation
Correct answer: C
Explanation
VRF is designed to isolate routing tables between different virtual networks. To enable communication between VRFs, route targets must be configured to allow the import and export of routes. Without route targets, VRFs will remain isolated, even if static routes are present. In this scenario, the lack of route target configuration is the root cause of the issue.
- A. Incorrect.
If static routes are incorrectly configured, communication issues may occur; however, the question does not explicitly state that the static routes are misconfigured. The issue likely lies elsewhere.
- B. Incorrect.
VRF Lite supports communication between VRFs, but it requires additional configuration, such as route targets. This is not the correct explanation for the issue.
- C. Correct.
A route target is used to control the import and export of routes between VRFs. Without configuring route targets, VRFs remain isolated, which explains why there is no communication between them.
- D. Incorrect.
VRF-aware routing protocols can be used, but they are not strictly required to enable communication between VRFs. Static routes can achieve the same goal when route targets are correctly configured.