200-301 Question 279
Single answerA network administrator has configured a static route on a router with the command ip route 10.10.20.0 255.255.255.0 192.168.1.1. During troubleshooting, the administrator notices that the route is not appearing in the routing table. What could be the most likely reason for this behavior?
- A
The interface leading to the next hop 192.168.1.1 is administratively down.
- B
The destination network 10.10.20.0/24 is already being learned dynamically.
- C
The next-hop IP address 192.168.1.1 is unreachable.
- D
The static route is missing the administrative distance parameter.
Show answer and explanation
Correct answer: C
Explanation
For a static route to be installed in the routing table, the next-hop IP address must be reachable. If the next-hop address is unreachable, the router will not add the route to the table, even if the static route configuration is correct. The scenario implies that the next-hop address 192.168.1.1 is unreachable, making this the most likely cause of the issue.
- A. Incorrect.
If the interface leading to the next hop is down, the route will not be installed in the routing table. However, the scenario does not mention any interface issues.
- B. Incorrect.
If the destination network is already being learned dynamically, the static route would still appear in the routing table unless the dynamic route has a lower administrative distance. This is not the most likely cause based on the scenario.
- C. Correct.
If the next-hop IP address is unreachable, the static route will not be installed in the routing table. This is the most likely cause in this case.
- D. Incorrect.
The administrative distance parameter is optional when configuring static routes. If it is omitted, the default administrative distance for static routes (1) is used.