As a network administrator of Company ABC, you've been requested to configure the internal clients ( to connect to a partner server on port 12345. Unfortunately, you discover that your ISP (R3) blocks traffic on that particular TCP port 12345 and allows only some well-known ports, including 8080.

After several discussions with the Partner Company, they have agreed to configure their server to listen on port 8080 for this purpose.

Now, it appears there's another problem: behind R1, the applications are already configured to use port 12345 and it cannot be changed. As a result, you've been requested to configure port redirection on the border router (R2) for all traffic going to server on port 12345 to be redirected to port 8080.

On the border router (R2) you already have NAT that is hidding the entire internal network behind the external interface of your router, as you can see below:

What command(s) you need on R2 so that traffic originating from your internal network going to external server will translate the port from 12345 to 8080 ?

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