Why is the default route using port2 not visible in the output of the second command?

The default route using port2 is not visible in the output of the second command primarily because it has a higher distance than the default route using port1. In networking, routing distance refers to the metric that routers use to determine the best path for traffic. Lower distance values indicate preferred routes. Consequently, if the default route on port1 has a lower distance value compared to the one on port2, the routing table will prioritize the route over port1. This means that the route associated with port2 will not appear in the output since it is not the active or preferred route for outbound traffic.

Other factors such as the status of the port or misconfiguration could play a role in route visibility, but the key reason related to routing protocols and metrics lies in the distance associated with each route. When multiple routes to the same destination exist, the one with the lower distance is favored, thus explaining the absence of the route through port2 in the command output.