This read-write object reports the primary routing metric for this route, with its meaning determined by the routing protocol in zhIpCidrRouteProto, and set to -1 when this metric isn't used by that protocol. Admins compare metric values across candidate routes to the same destination to understand why the routing table selected this particular route as best. A zhIpCidrRouteMetric1 of -1 on a statically configured route confirms that protocol, netmgmt, doesn't use this primary metric field, unlike a dynamically learned OSPF or RIP route which would populate it.