Cisco route selection

1. How are routes selected?
2. What does the route 0.0 0.0 0.0 0.0 mean?
3. What is the best path selection in Cisco OSPF?
4. What is default route selection?

How are routes selected?

The three attributes for Route Preference are the Route Specificity, the Administrative Distance, and the Metric. If multiple routes exist and all three of these attributes are identical, the Router will load balance across the available paths.

What does the route 0.0 0.0 0.0 0.0 mean?

In IPv4-based routing, 0.0. 0.0 serves as a default route. This means no particular address has been designated in the routing table as the next hop in the packet's path to its final destination.

What is the best path selection in Cisco OSPF?

Since Cisco IOS release 15.1(2)S, Cisco uses the path selection order from RFC 3101, which obsoletes RFC 1587. This means that it prefers N1 routes before E1 and N2 over E2 routes. In other words, the preferred path list is O > O IA > N1 > E1 > N2 > E2.

What is default route selection?

A default route is the route that takes effect when no other route is available for an IP destination address. If a packet is received on a routing device, the device first checks to see if the IP destination address is on one of the device's local subnets.