What condition must NOT exist for FortiGate to add a static route?

For FortiGate to successfully add a static route, one critical condition is that the outgoing interface must be active and properly configured. Therefore, if the interface is inactive, the FortiGate will not be able to utilize that route for packet forwarding. This makes option about the interface being inactive a valid condition that must not exist for a static route to be added.

Additionally, a significant aspect of static routing lies in route distance. FortiGate uses administrative distance to determine the preference of routes. If another route with a shorter distance exists in the routing table, it indicates that there is an already preferred route which may take precedence over the new static route being added.

Thus, for the successful configuration of a static route, it is vital that there is no other route with a shorter distance that may conflict with the new route. Overall, the static route addition will fail if the interface is down or inactive, verifying that having an operational outgoing interface is a critical requirement.