Independent, multiple OSPF processes are entered on the same router, and the processes have the same destination route. Which OSPF process is used?

While OSPF uses cost as a metric, when comparing routes from different OSPF processes with the same administrative distance, the router generally uses the first route installed rather than continuously comparing metrics across independent processes for the exact same route.

Load balancing typically occurs for equal-cost paths within a single routing protocol instance or between different protocols if explicitly configured, but not automatically between independent OSPF processes for identical routes.

If multiple OSPF processes on a router learn the same destination route, each maintaining its own database, the router's main IP routing table will retain the route that was initially installed by one of the OSPF processes. Since all OSPF processes have the same administrative distance (110), subsequent identical routes are typically not installed if one already exists.

Route selection prioritizes the longest prefix match when comparing different subnets; however, for identical destination routes (same prefix and length), prefix length is not a tie-breaking factor.