You want to configure two static routes: one that references a zone and a second...

FortiOS supports both route types described in the question. The FortiOS 7.6 Administrator Study Guide states that a static route can reference one or more SD-WAN zones and that FortiOS consequently installs an individual route for every member of the selected zone. It also states: “Alternatively, you can configure per-member static routes for more granular control over traffic.” Therefore, options A and B are incorrect. Fortinet’s official configuration guidance likewise shows static routes referencing an SD-WAN zone .

The relevant duplicate-route restriction is based on the destination prefix. Fortinet courseware explains: “FortiOS doesn’t allow you to configure a static route for the same destination that references an interface.” Accordingly, a route referencing an SD-WAN zone and another route referencing one of that zone’s members cannot use identical destination subnets. They can use different or overlapping destination prefixes—for example, a less-specific route through the zone and a more-specific route through the individual member. The source subnets are not the required differentiator, eliminating option D.

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