#Fortigate201F Interface that fortigate use for policy

[INTI]

How to make a Nat for all traffic to some port for internal fortigate?

For Example port 1 ip is 192.168.0.2, when fortigate use it i want to nat it as 192.168.1.2. I can do this when the source from other port, but i cant find a way to do this for internal fortigate connection.

[AlexC-FTNT]

Are you talking about VLANs? 
You can easily enable (one or more) secondary IPs on the LAN interface, but may not be what you are looking for. If your secondary IP for port1 is 192.168.1.2, FortiGate will reply to this IP. You can also use it to send traffic.