his is a small example on how to configure policy routes (also known as policy-based forwarding or policy-based routing) on a Fortinet firewall, which is really simple at all. Only one single configuration page and you’re done.
In my lab, I have a static default route to the wan1 interface. On the wan2 interface, there is a simple DSL connection to the Internet which shall be used for http/https traffic from the users. That is: Everything from the users IP segment (192.168.161.0/24) to the destination ports 80 and 443 shall be forwarded to this DSL connection. But an exemption is still needed: If the destination is on the internal LAN, the connection should not be policy routed. (Of course, appropriate policies must be in place, too.) The configuration is done under Router -> Static -> Policy Routes:
That’s it. In the Forward Traffic Log, it is easy to see which destination interface is used, dependent on the destination port: