Cisco Certified Network Associate (CCNA) Practice Exam

Which command displays all OSPF routers, number of areas, number of routers in each area, and network links between them?

1. show ip ospf database

2. show ip ospf neighbors

3. show running-config

4. show version

The correct answer is: show ip ospf database

The command that displays all OSPF routers, the number of areas, the number of routers in each area, and the network links between them is "show ip ospf database." This command provides a comprehensive view of the OSPF routing information within the network. When you issue this command, it retrieves the OSPF link-state database (LSDB) from the router. The LSDB contains detailed information about all the OSPF routers and their relationships within the configured OSPF areas, including the number of areas and links that connect them. It essentially presents a detailed structure of how OSPF is operationalized across the network, showing router IDs, area IDs, and the types of links (such as point-to-point or broadcast) that exist between different routers. In contrast, the other options do not deliver the same comprehensive OSPF routing information. "Show ip ospf neighbors" focuses specifically on the OSPF neighbor relationships, providing details about directly connected OSPF routers and their states but not the overall network topology. "Show running-config" displays the current configuration of the router but does not provide specific operational details about OSPF routers or their relationships. "Show version" offers information about the router's hardware