Cisco Certified Network Associate (CCNA) Practice Exam

What is the command to summarize routes on an OSPF ABR?

1. (config-router)#area AREA NUMBER summary IP NETWORK ADDRESS AND SUBNET MASK

2. (config)#router ospf PROCESS NUMBER

3. (config-router)#area AREA NUMBER range IP NETWORK ADDRESS AND SUBNET MASK

4. (config-router)#network IP NETWORK RANGE

The correct answer is: (config-router)#area AREA NUMBER range IP NETWORK ADDRESS AND SUBNET MASK

The command to summarize routes on an OSPF Area Border Router (ABR) is the one that specifies the area and the range of networks that you want to summarize. This command is specifically designed to create a summary route that represents a range of more specific routes. In OSPF, summarization is typically performed at the ABR to reduce the size of routing tables and improve efficiency in routing. The correct command includes the area number for which you're summarizing and the network address along with the subnet mask that defines the range of networks being summarized. By implementing this command, a single route is advertised in the OSPF database instead of multiple routes that could overwhelm the routing system. The other options provided do not serve this purpose: one option concerns configuring the OSPF process, another focuses on defining network ranges, and one addresses area operation but not in the context of summarization. Thus, the choice that encapsulates summarizing OSPF routes effectively at an ABR is the correct command.