200-301 Question 285
Single answerYou are configuring a network with multiple routing protocols on a router. The router receives the same route (destination network) from three different routing protocols: OSPF, EIGRP, and RIP. Which routing protocol's route will be installed in the routing table by default, assuming all metrics are equal and no modifications to administrative distances have been made?
- A
OSPF
- B
EIGRP
- C
RIP
- D
The router will load balance across all three routes
Show answer and explanation
Correct answer: B
Explanation
Administrative distance is a measure of the trustworthiness of a routing source. Lower administrative distance values are preferred over higher ones. By default, EIGRP has an administrative distance of 90, OSPF has 110, and RIP has 120. Since EIGRP has the lowest administrative distance among the three, its route will be installed in the routing table.
- A. Incorrect.
OSPF has an administrative distance of 110, which is higher than EIGRP's administrative distance of 90, meaning it is less preferred.
- B. Correct.
EIGRP has an administrative distance of 90, which is lower than both OSPF's and RIP's administrative distances, making it the most preferred by default.
- C. Incorrect.
RIP has an administrative distance of 120, which is the highest among the three protocols, making it the least preferred.
- D. Incorrect.
The router does not load balance in this scenario because the administrative distances are different, and only the route with the lowest administrative distance will be installed.