300-440 Question 64
Single answerA network engineer is troubleshooting EIGRP routing in a network. Router R1 is unable to reach a specific destination network, and upon inspection, it is observed that there is no feasible successor for the route. Which of the following is the MOST likely reason for this issue?
- A
The reported distance of the backup route is higher than the feasible distance of the successor route.
- B
The route is stuck in active because the query reached its maximum hop count.
- C
The successor route was removed due to an administrative shutdown of the interface.
- D
The feasible condition is satisfied, but the router is unable to install the route in the routing table.
Show answer and explanation
Correct answer: A
Explanation
In EIGRP, a feasible successor is a backup route that satisfies the Feasibility Condition (FC). The FC states that the reported distance (RD) of the backup route must be less than the feasible distance (FD) of the current successor route. If no route meets this condition, there will be no feasible successor, which can impact network convergence and redundancy.
- A. Correct.
This is the correct answer. For a route to qualify as a feasible successor, its reported distance must be less than the feasible distance of the current successor route. If this condition is not met, there will be no feasible successor.
- B. Incorrect.
While a route stuck in active indicates an issue, it’s not relevant to the lack of a feasible successor. Stuck in active occurs when a query for an alternate route fails to find a response within the allowed time.
- C. Incorrect.
The removal of the successor route would lead to the route becoming invalid, but it does not directly explain why there is no feasible successor.
- D. Incorrect.
If the feasible condition is satisfied, the route would be installed as a feasible successor. This statement is incorrect and contradicts the premise of the question.