| Exam 200-120 | Question id=21 | IP Routing Technologies |
Which type of EIGRP route entry describes a feasible successor?
| A. |
a backup route, stored in the routing table | |
| B. |
a primary route, stored in the routing table | |
| C. |
a backup route, stored in the topology table | |
| D. |
a primary route, stored in the topology table |
Feasible Successors:
A destination entry is moved from the topology table to the routing table when there is a feasible successor. All minimum cost paths to the destination form a set. From this set, the neighbors that have an advertised metric less than the current routing table metric are considered feasible successors.
Feasible successors are viewed by a router as neighbors that are downstream with respect to the destination. These neighbors and the associated metrics are placed in the forwarding table.
When a neighbor changes the metric it has been advertising or a topology change occurs in the network, the set of feasible successors may have to be re-evaluated. However, this is not categorized as a route recomputation.