Static Nat is highly useful in situations where we have to make our internal network accessible from the public network. For example, if have a web server we can statically map the server’s IP address with public IP address so that it can become accessible from the internet.
We can also make multiple static Nat entries if we want more devices to be accessible from the internet. Additionally, we can map the port numbers in a static Nat. So, if the request comes from the internet for a specific server then the traffic is forwarded to the port number, which is assigned in the static mapping. This way we can use one public IP with the multiple static entries.
In this lab, we will perform a basic Nat configuration and map private IP with the public IP address.
Static Nat is very simple to configure on a Cisco router. We have to label the interface with Nat inside and outside, and then map the private IP with public IP one to one.
Static NAT example
1. label the interfaces
2. Enable static NAT
Router0(config)#interface fastethernet 0/0
Router0(config)#ip nat inside
Router0(config)#interface fastethernet 0/1
Router0(config)#ip nat outside
Router(config)#ip nat inside source static 192.168.1.1 220.127.116.11