Scenario 1: FortiGate has public IP address, FortiManager is behind NAT

In this scenario, the FortiManager administrator must configure the FortiGate’s IP address of hostname during the Add Device operation. Once complete, the FortiManager will initiate a connection to the FortiGate to perform authentication. Once authentication is successful, the FortiGate is immediately registered on the FortiManager and the unit can begin management functions on the FortiGate.