Port forwarding not working on WAN2 (but did!)

[icom]

se attached picture. 

I'am trying to port forward some traffic via WAN2 as a backup via 4G modem - but it dont seems to work. When connecting my computer directly to the 4G modem with same IP adress as the WAN2 fortigate, port forwarding on the 4G i working. 

If i then connect my computer to WAN2 with same IP adress as the 4G, port forwarding is working.

In my lab this worked just perfectly before installing this at the client location. In my lab i only testet with WAN2/4g Connected..

When I installed the fortigate at the client we first tried with only WAN2/4g connected, and everything worked. Then connected WAN1 to see it switch. port forwarding is working on WAN1. 

We need this only as failover and not load balancing. 

Any clues? 

[Leen]

Hi if you don’t yes routing protocols the easiest way is to setup a ping server on fortigate. If the ping to either wan port is unsuccessful it will change the routing cost up so that wan2 will get a lower cost and the default route will send traffic over wan2. Once wan1 comes back the ping server will success and lowers cost on primary link. All traffics c will default back to wan1