Cisco Certified Network Associate (CCNA) Practice Exam

Which command helps confirm if a password is set on a serial interface?

1. #show interfaces

2. #show running-config

3. #show configuration

4. #show access-lists

The correct answer is: #show running-config

The command that confirms if a password is set on a serial interface is the command used to display the currently running configuration of the device, which includes configuration details for all interfaces, including any password settings. When executed, this command provides a comprehensive output that shows various configurations such as interface settings, routing configurations, and security settings. In the context of a serial interface, this command will include particular lines indicating whether a specific password is configured for both physical and virtual lines, such as the console or virtual terminal (VTY) lines. This allows you to verify the existence of passwords and the security configurations associated with the serial interface. Other commands such as those that display interfaces or access lists may provide information about network status or traffic filtering but would not specifically confirm password settings on any interfaces. Therefore, this command is fundamental for network administrators needing to audit or verify password protections on their equipment.