300-410 Question 26
Single answerA network engineer has configured manual summarization on Router A for EIGRP. However, some routes in the summarized range are not reachable from other routers in the network. Upon reviewing the configuration, the engineer finds that the manual summary address overlaps with one of the subnets already advertised by another router. What should the engineer do to resolve this issue?
- A
Modify the manual summary address on Router A to a non-overlapping range.
- B
Enable auto-summarization on Router A to automatically resolve the conflict.
- C
Remove the manual summarization configuration and rely solely on specific routes.
- D
Configure a distribute-list to filter the overlapping subnet from being advertised by the other router.
Show answer and explanation
Correct answer: A
Explanation
When using manual summarization, it is crucial to ensure that the summary address does not overlap with existing subnets in the network. Overlapping addresses can create routing conflicts and cause reachability issues. The best approach is to modify the manual summary address to avoid any overlap while maintaining efficient route summarization.
- A. Correct.
Correct: Modifying the manual summary address to a non-overlapping range ensures the summary does not conflict with existing routes, resolving reachability issues.
- B. Incorrect.
Incorrect: Enabling auto-summarization might introduce additional summarization conflicts, especially in modern discontiguous networks, and is not a recommended solution.
- C. Incorrect.
Incorrect: Removing manual summarization entirely might resolve the issue, but it is not an optimal solution for scalability and efficient routing.
- D. Incorrect.
Incorrect: A distribute-list could prevent the advertisement of the overlapping route but is not the best practice to resolve summarization conflicts.