300-440 Question 48
Select 3A network engineer is troubleshooting an EIGRP issue where an EIGRP neighbor relationship between two routers in a VRF is not forming. Both routers are configured with named EIGRP. Upon reviewing the configuration, the engineer finds that the VRF name is consistent on both routers. What could be the cause of the issue?
- A
The EIGRP AS numbers are mismatched between the two routers.
- B
The EIGRP authentication keychains are not configured or do not match.
- C
The interfaces participating in EIGRP are not assigned to the same VRF.
- D
The EIGRP network commands are missing from the configuration.
- E
EIGRP is not enabled globally on one of the routers.
Show answer and explanation
Correct answers: A, B, C
Explanation
For EIGRP neighbor relationships to form in a VRF, the AS numbers must match, authentication keychains (if configured) must match, and the interfaces involved in EIGRP must be assigned to the same VRF. Misconfigurations in any of these areas will prevent the adjacency from forming. Network commands are not required in named EIGRP as interface-level configurations can be applied directly, and EIGRP is enabled on a per-VRF basis rather than globally.
- A. Correct.
Correct: EIGRP AS numbers must match between neighbors for the relationship to form, even in a VRF environment.
- B. Correct.
Correct: EIGRP authentication keychains must match between neighbors. If they do not, the adjacency will not form.
- C. Correct.
Correct: Interfaces must be assigned to the same VRF for EIGRP to work within a VRF instance. This could prevent the adjacency from forming.
- D. Incorrect.
Incorrect: Named EIGRP does not require network commands, as interfaces can be directly configured in the named mode.
- E. Incorrect.
Incorrect: EIGRP is enabled at the VRF level, not globally, when working within a VRF. This would not cause the issue described.