300-440 Question 79
Select 3A network engineer is troubleshooting routing issues in an OSPF-enabled network. The engineer notices that a specific route is being ignored in favor of another route, even though both have the same administrative distance. Upon further inspection, the engineer identifies that the issue is related to the OSPF metrics. Which of the following factors could influence the OSPF metric and cause this discrepancy?
- A
Bandwidth of the outgoing interface
- B
Delay on the outgoing interface
- C
The administrative distance of OSPF
- D
Cumulative cost of the route based on interface metrics
- E
Hop count to the destination
Show answer and explanation
Correct answers: A, B, D
Explanation
OSPF calculates its metric based on the cost, which is influenced by factors like interface bandwidth and delay. The cumulative cost of all interfaces in the path determines the route preference. Administrative distance and hop count are unrelated to OSPF metrics, as the former is used for comparing different routing protocols and the latter is specific to RIP.
- A. Correct.
Correct. OSPF uses the bandwidth of the outgoing interface as part of its metric calculation. Interfaces with higher bandwidth are preferred.
- B. Correct.
Correct. Delay is another factor that influences the OSPF metric. Higher delays result in higher costs, making routes less preferred.
- C. Incorrect.
Incorrect. Administrative distance is not part of OSPF's metric calculation; it is used to compare routes from different routing protocols.
- D. Correct.
Correct. The OSPF metric is the cumulative cost of the route, calculated by summing the costs of all outgoing interfaces along the path.
- E. Incorrect.
Incorrect. Hop count is used as a metric in RIP, not in OSPF.