Cisco Certified Network Associate (CCNA) Practice Exam

Which command is used to change the cost of an OSPF interface?

1. ipv6 ospf cost NUMBER

2. cost ipv6 ospf NUMBER

3. ospf cost set NUMBER

4. set ospf cost NUMBER

The correct answer is: ipv6 ospf cost NUMBER

To change the cost of an OSPF (Open Shortest Path First) interface, the command used is "ipv6 ospf cost NUMBER." This command allows network administrators to manually adjust the cost of a specific OSPF interface, which influences the OSPF route selection process. The cost is a metric used by OSPF to determine the best path for routing data; a lower cost generally indicates a preferred shorter path. When configuring OSPF, especially in larger networks, you might want to optimize the routing by adjusting the interface cost on specific links. The "NUMBER" parameter you provide defines the new cost, allowing for greater control over how the OSPF protocol prioritizes traffic. The other options do not conform to the accepted syntax for OSPF configuration. The correct command format not only adheres to Cisco IOS command structure but also accurately directs the configuration context to OSPF and is specific to adjusting costs on interfaces, ensuring that the intended changes take effect appropriately.