Chapter 18 Troubleshooting : ­Verifying FortiGate admin access security : Change the default administrative port to a non-standard port
  
Change the default administrative port to a non-standard port
Administration Settings under System > Admin > Settings or config system global in the CLI, enable you to change the default port configurations for administrative connections to the FortiGate unit for added security. When connecting to the FortiGate unit when the port has changed, the port must be included. For example, if you are connecting to the FortiGate unit using HTTPS over port 8081, the url would be https://192.168.1.99:8081
If you make a change to the default port number for HTTP, HTTPS, Telnet, or SSH, ensure that the port number is not used for other services.