Can you understand how the routing will work with this config?
LAN1(10.10.10.0/24) to 0.0.0.0 through NAT (interface ip 126.96.36.199) on interface LAN1 to WAN1 (ISP 1)
LAN2(10.20.20.0/24) to 0.0.0.0 through NAT (interface ip 188.8.131.52) on interface LAN2 to WAN2 (ISP 2)
0.0.0.0/0 via 184.108.40.206, interface WAN1, distance 1 priority 0
0.0.0.0/0 via 220.127.116.11, interface WAN2, distance 1 priority 0
Would it work without a traffic policy?
What we need to do it's two network go through different ISPs.
I think ECMP will be used since the default routes have the same distance and priority. Traffic will be loadbalanced between the two WAN links.
In this case, some traffic might be dropped (routing decision is made before policy matching).
For example, if traffic comes from LAN2 and the Fortigate decides to route traffic through WAN1, no Firewall policy will match.
For your scenario, the easiest way is to use SD-WAN, then you can add SD-WAN policies to route LAN1 traffic through WAN1 and LAN2 traffic through WAN2.
You can also use policy routes, use both default routes but with different priorities, like this only one route will be used by default, then add a policy route to route traffic through the other interface.
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