What are three key routing principles of SD-WAN?

FortiGate requires an eligible SD-WAN member to have a valid route to the destination in the forwarding information base (FIB). Therefore, a member without such a route cannot be selected, making B correct. FortiGate also performs a FIB best-match check when evaluating an SD-WAN rule. If the resolved best-route interface is not an SD-WAN member, FortiGate skips that SD-WAN rule, confirming D.

ISDB routes operate as policy routes and are evaluated before SD-WAN rules, so C is also correct. A static route does not automatically bypass SD-WAN; static routes can provide the FIB routes required by SD-WAN members. Likewise, directly connected routes do not categorically take precedence over every SD-WAN rule. The applicable behavior depends on FIB resolution and whether the resolved interface belongs to SD-WAN.

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