Verifying route redundancy
Bring down WAN1 and then check the routes on the two FortiGate units.
FortiGate 1:
FGT1 # get router info routing-table ospf
FGT1 # get router info routing-table ospf
O*E2 0.0.0.0/0 [110/10] via 10.183.0.187, wan2, 00:00:06
O 192.168.182.0/23 [110/210] via 10.183.0.187, wan2, 00:00:06
FortiGate 2:
FGT2 # get router info routing-table ospf
O 10.160.0.0/23 [110/210] via 10.183.0.57, wan2, 00:00:14
The WAN2 interface is now in use on both units.