To provide an example of port redirection, we will modify the rule created in this recipe so it uses a destination port other than 22. To modify the rule, do the following:

1. Navigate to Firewall | NAT.
2. Click on the Edit icon for the rule we previously created.
3. Change the Destination port range to a port other than 22 (select Other in the drop-down menu and then type an arbitrary port number in the custom edit box; for example, 12345).
4. When you are done making changes, click on the Save button.
5. Click on the Apply Changes button.

By changing the Raspberry Pi SSH port forwarding rule, we can now SSH into our Raspberry Pi using whatever port we entered in step 3. Thus, anyone running a port scanner on our site will not see port 22 open and won’t know what service is running on the open port.