EIGRP uses the DUAL algorithm to find the least and efficient route to the destination. DUAL stands for Diffusing Update Algorithm. EIGRP is compatible with the IGRP routers. EIGRP provides the instant synchronization of all the routers. DUAL contains the critical information that the routers use to make the least-cost routes towards the destinations.
The key features of the Enhanced Interior Gateway Routing Protocol includes the fast convergence, support for partial updates, compatibility with other protocols like IGRP and the support for the subnet masks of the variable length. The data packets in the EIGRP are delivered using RTP (Reliable Transport Protocol), which ensures the reliable and guaranteed delivery of the data packets.
EIGRP is associated with different metrics like reliability, total delay, load, and minimum path maximum transmission unit. Routers that use the EIGRP, stores the routing tables of the neighbors. EIGRP consists of the following components.
- Reliable Transport Protocol
- Neighbor Discovery/Recovery
- Protocol Dependent Modules
- DUAL Finite State Machine
Each router that uses the EIGRP stores the information of the neighbors. Each router sends out the hello packets periodically. In this way, all the routers gets updated and exchange the routing tables with each other. If a router doesn’t send the hello packets within the specific period of time, it considered to be inoperative. EIGRP can be configured on a router by using the following command.
Router# conf t
Router(config)# router eigrp
Router(config-router)# network 192.168.10.20
EIGRP Troubleshooting Commands
You can check and verify the functionalities of the EIGRP by using the following commands.
- show ip interface brief
- show ip route eigrp
- show ip eigrp neighbors
- show ip eigrp traffic
- show ip route