Route selection order
policy routes → the FIB (most specific prefix, then lowest distance, then lowest priority, then ECMP) → SD-WAN rules sit on top for their members
For traffic the FortiGate is forwarding:
1. Policy routes (config router policy) are checked first — source/dest/protocol/port match, and they can force an egress interface/gateway before the routing table is even consulted.
2. Then the routing table (FIB): longest-prefix match wins; among equal prefixes, lowest administrative distance; among equal distance, lowest priority; still equal → ECMP.
3. SD-WAN rules govern which member carries a session among the SD-WAN members, layered on this.
get router info routing-table all shows the FIB; diagnose firewall proute list shows policy routes.