350-401 Question 384
Single answerA network engineer is troubleshooting an EIGRP (classic mode) routing issue. OSPF and EIGRP are running on the same router in the global routing table, and some routes learned via EIGRP are not appearing in the routing table. On inspecting the EIGRP neighbor table, all neighbors are in the 'FULL' state. The show ip route command reveals that OSPF routes have a lower administrative distance than EIGRP routes, causing EIGRP routes to be overridden. What is the most effective way to resolve this issue?
- A
Increase the administrative distance of OSPF on the router.
- B
Redistribute OSPF routes into EIGRP with a higher metric.
- C
Configure route filtering to prevent OSPF routes from being learned.
- D
Change the EIGRP administrative distance to be lower than OSPF.
Show answer and explanation
Correct answer: D
Explanation
The issue occurs because OSPF has a lower administrative distance (default 110) than EIGRP's external routes (default 170). By lowering the administrative distance of EIGRP, the router will prefer EIGRP routes over OSPF routes, resolving the issue without needing to modify OSPF or implement route filtering. This approach preserves the integrity of both routing processes while aligning with best practices.
- A. Incorrect.
This is not the most effective solution since increasing the administrative distance of OSPF would require changes to multiple OSPF routers in the network, potentially causing other routing issues.
- B. Incorrect.
Redistributing OSPF routes into EIGRP with a higher metric does not address the issue of administrative distance, and it might lead to suboptimal routing or routing loops.
- C. Incorrect.
While filtering OSPF routes prevents them from being learned, it is not a scalable solution in a network where OSPF is also needed for other purposes.
- D. Correct.
Changing the administrative distance of EIGRP to be lower than OSPF ensures that EIGRP routes are preferred over OSPF routes without impacting the overall network design.