Cisco Certified Network Associate (CCNA) Practice Exam

What command is used to configure a static ARP entry in Cisco IOS?

1. (config)#arp IP ADDRESS MAC ADDRESS arpa

2. (config)#ip http authentication

3. (config)#logging trap

4. (config)#exec-timeout TIME

The correct answer is: (config)#arp IP ADDRESS MAC ADDRESS arpa

The command used to configure a static ARP entry in Cisco IOS is indeed the one that follows the format of specifying an IP address and a MAC address along with the "arpa" protocol identifier. This command allows the network administrator to manually create a mapping between an IP address and its corresponding MAC address, which is stored in the device's ARP table. Static ARP entries are useful to prevent ARP spoofing or to ensure that a specific device's MAC address remains associated with a given IP address regardless of any dynamic changes that might occur in the network. By using this command, the administrator can ensure that communication with important devices remains stable and predictable. The other commands listed do not pertain to the configuration of ARP entries. For example, the command related to HTTP authentication would be used in the context of securing web access on a device, while the command associated with logging deals with the level of logging notifications sent to a logging server. Lastly, the exec-timeout command is used to set the timeout for user sessions in the CLI, which also has no relation to ARP table configurations.