What is the default route preference for OSPF internal?

In OSPF, the default route preference for internal routes is set to 10. This default preference applies to OSPF routes that originate from within the OSPF area, which are known as internal routes. When the OSPF process considers multiple routes to a destination, the route with the lowest preference value is preferred. Therefore, internal OSPF routes with a preference of 10 will be prioritized over routes with higher preference values.

Understanding this default preference is crucial for network design and troubleshooting, as it influences the routing decisions made by OSPF. Given that OSPF uses cost as its metric to select the best path, the preference values serve as an additional layer of control in route selection, allowing OSPF to manage how traffic flows through the network.

In contrast, preference values for external routes introduced into OSPF (from another routing protocol via redistribution) and other route types will differ, and those differences can lead to other routes being selected based on their respective metrics and preferences.