Cisco Certified Network Associate (CCNA) Practice Exam

Which command confirms that an ACL has been configured on a router interface?

1. show access-lists

2. show ip interface INTERFACE NUMBER

3. verify acl configuration

4. show ip access-list

The correct answer is: show ip interface INTERFACE NUMBER

The command that confirms that an Access Control List (ACL) has been configured on a router interface is indeed to display the status of that specific interface. When you use the command to show the IP interface configuration, it will provide detailed information about the interface, including any ACLs that have been applied to it. This allows you to see whether an ACL is present on inbound or outbound traffic for that interface. While the other options provide useful information, they don't specifically confirm ACL configurations on a per-interface basis. For example, one command lists all ACLs configured across the router, but it doesn’t link them to individual interfaces. Another option suggests verifying ACL configuration, but that isn't a valid command in Cisco IOS. The last choice, similar to the first, shows access lists but not their application to specific interfaces. Thus, using the command to check the IP interface configuration gives you the targeted information needed to confirm ACL application directly related to that interface.