You may use the following method to configure Enhanced Interior Gateway Routing Protocol (EIGRP) on your Cisco router(s).
Begin by entering privileged exec mode on your Cisco router by using the enable command.
Enter global configure mode by using the command configure terminal.
Type the command router eigrp [as] where [as] is the autonomous system number. The autonomous system number may be any number between 1 – 65535. The important part to remember is that the autonomous system numbers must be identical on each router in order for the EIGRP routers to exchange routing information.
Use the network x.x.x.x command to advertise the networks of your choosing where x.x.x.x is the classful address range of that particular network. In this particular example this router has 172.16.20.0/24 (ethernet 0) and 172.16.25.0/30 (serial 0) configured so I used the classful address range 172.16.0.0.
After configuring the other router in this example, with EIGRP and autonomous system number 250, we can now verify our configuration with the show ip protocols, show ip route and ping commands.
The show ip protocols command will display information regarding each routing protocol that is configured on your router. The show ip route command will display the routing table on your router. In this example, the C represents directly connected networks and the D represents the EIGRP advertised routes. Lastly, I used the ping command to verify network connectivity between the two routers.