Fortinet Updated FCSS_SDW_AR-7.4 Exam Questions and Answers by lorelai

Policy 3 points traffic To = HUB1-VPN1, which is an SD-WAN member interface. In SD-WAN you must reference the SD-WAN zone (the logical interface) in policies, not its member tunnels. Change the policy’s To interface to the zone HUB1, and the install will succeed.

Fortinet outlines key SD-WAN routing principles:

"Policy routes are always evaluated before SD-WAN rules, meaning if a policy route matches, SD-WAN steering is bypassed. If the best route for a destination is not via an SD-WAN member, SD-WAN rules do not apply, and members are ignored if they lack a valid route. This hierarchy ensures traffic always follows the most deterministic and valid path according to configuration."

Understanding these principles is critical for correct SD-WAN and routing integration.

This configuration demonstrates a typical IPsec setup for SD-WAN overlays where the hub side requires a manually defined tunnel IP address, and the spoke can be flexibly configured, including interoperability with third-party IPsec devices. As described in the Fortinet SD-WAN Architect Guide: “For some overlays, the tunnel interface IP is configured statically on the hub side, which allows more control over overlay subnetting and facilitates the use of user-defined overlay IP addresses. This approach is also a requirement for compatibility with non-FortiGate endpoints, such as third-party IPsec devices that may not support dynamic address assignment via IKE or proprietary mechanisms.” This enables hybrid SD-WAN environments and advanced designs involving external partners or cloud services. Overlay IP flexibility is critical for route control and segmentation.