Cisco CCNA Exam 200-125: Troubleshooting Ethernet Interface Configuration Error

Reason for Ethernet Interface Configuration Error

Prev Question Next Question


A network administrator receives an error message while trying to configure the Ethernet interface of a router with IP address Which statement explains the reason for this issue?



Click on the arrows to vote for the correct answer

A. B. C. D.


The error message suggests that there is an issue with configuring the Ethernet interface of a router with the IP address This means that the IP address is using a subnet mask of, which results in a network address of and a broadcast address of Therefore, options A and C can be ruled out.

Option B, which suggests enabling VLSM-capable routing protocols, does not address the issue at hand, as the problem is related to the IP address configuration on the Ethernet interface, rather than the routing protocol.

Option D correctly explains the reason for the issue. The IP address is a network address, which means that it cannot be assigned to any device, including a router interface. Network addresses are reserved for identifying the network itself, while host addresses are used to identify individual devices on the network. In this case, the host addresses range from to, leaving the network address and broadcast address unassignable.

Therefore, the correct answer is D.