Cisco Certified Network Associate (CCNA) Practice Exam

Which command is used to configure a static NAT mapping on a router?

1. (config)#ip nat source static PRIVATE IP ADDRESS AND PUBLIC IP ADDRESS

2. (config)#ip nat inside source list ACCESS LIST NUMBER

3. (config)#access-list ACL NUMBER permit host PRIVATE IP ADDRESS

4. (config)#ip nat pool POOL NAME

The correct answer is: (config)#ip nat source static PRIVATE IP ADDRESS AND PUBLIC IP ADDRESS

The command to configure a static NAT mapping on a router is indeed the one that specifies both the private IP address and the public IP address. This command creates a direct mapping between a specific private IP address (typically used within a local internal network) and a public IP address (used for external access on the internet). By using this command, the router is instructed to always translate the given private IP address into the specified public IP address every time traffic is sent from the private network to the internet. This is essential for scenarios where a specific internal server (like a web server) needs to be reliably accessible from external networks with a consistent public address. The other options represent different commands or configurations used in the context of NAT but do not directly configure static NAT mappings. One of them is related to defining a NAT access list, while another deals with defining a NAT pool for dynamic mappings. The access list command serves to permit certain traffic rather than establishing a static mapping, and the command for NAT pool focuses on a range of addresses rather than direct one-to-one mappings.