A FortiGate has several routes whose destination prefixes could match the same packet. In what order does FortiGate apply the route-selection criteria to determine the best route?
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A
Most specific prefix first, then the lowest administrative distance, then metric and priority
Correct
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B
Lowest administrative distance first, then the most specific prefix, then priority
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C
Lowest priority value first, then the lowest administrative distance, then the most specific prefix
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D
Lowest metric first, then the most specific prefix, then the administrative distance
Explanation
The best route is the most specific route to the destination (longest prefix match). Only when FortiGate finds duplicate routes - multiple routes to the same destination - does it use route attributes as tiebreakers: administrative distance is the first tiebreaker, metric breaks ties, and priority breaks ties between equal-distance duplicate static routes. The remaining options invert this order: distance, metric, and priority are never compared across routes of different prefix lengths, because those routes are not duplicates and are not competing for the same routing table entry.