EIGRP Lab4 - Configuring EIGRP Unequal-Cost Paths

【Lab objectives】

1. Learn balance conditions of EIGRP unequal-cost

2. Learn how to change EIGRP metric value

3. Learn EIGRP AD, FD, FC, Successor, and FS

【Lab Topology】

【Lab steps】

1. Configure IP addresses of every router, and use ping command to confirm the direct interface connectivity of every router.

2. Configure on three routers EIGRP auto system number as 50

3. Observe the route for R1 to access 192.168.1.0/24 network of R3

4. To improve network transmission, we have to use route with the next hop of 172.16.1.2, i.e. use another path with different metric value to balance load.

5. If another path is needed, we have to make sure that R1 becomes the feasible successor (FS) for R1 to access 192.168.1.0/24 network. To become FS, Feasible condition (FC) are required.

6. Check EIGRP topology on R1; R2 cannot be found in R1 topology.

7. Check the complete topology

8. Confirm FC (feasible condition) formula:

AD of secondary-best route < FD of best route (Successor) = Feasible Successor

From this instance we get this conclusion:

The Distance that R2 access 192.168.1.0 network < 156160

9. Configure EIGRP metric of R2, and make sure that R2 become FS of R1

10. Check R1 topology:

11. With the following formula, configure variance value of R1 EIGRP

FD of FS route < FD of best route (Successor) * Variance

With the formula we get:

2300416 < 156160 * x

x≈14.73

12. First configure the variance value as 14, then test and observe the routing table.

13. Change the variance value to 15 and observe the routing table.

14. Lab finishe.

Hope to helpful for you!