This is the primary routing metric assigned to the route, with its meaning defined by whichever routing protocol is named in the route's aniDevRouteProto value, or -1 if the metric isn't used. Admins use it to judge route preference and cost when several routes exist to the same destination, since a lower or higher number (protocol-dependent) signals the preferred path. For example, an OSPF-learned route might report aniDevRouteMetric1 as 20 to reflect OSPF cost, while a statically configured route not using this metric would show -1.