EIGRP Metric: Steering Paths by Tuning Delay

Bundle lab

Tune EIGRP path selection by manipulating cumulative delay. Three routers (R1-R2-R3) form EIGRP 100 adjacencies over three /30 point-to-point links. R3 originates 192.168.30.0/24 on Loopback0. You will enable EIGRP and then increase delay on R1’s direct link to R3 so R1 prefers the indirect path via R2 to reach 192.168.30.0/24. Two Alpine hosts validate end-to-end reachability and path choice.

Learning objectives

• Enable EIGRP with a consistent AS (100) and no auto-summary across three routers
• Understand EIGRP metric composition: minimum bandwidth and cumulative delay
• Steer R1’s route to 192.168.30.0/24 via R2 by increasing interface delay on R1’s direct link to R3
• Validate successor/feasible successor selection with show ip eigrp topology
• Confirm path selection using show ip route eigrp and data-plane traceroute from hosts

Troubleshooting focus

• If adjacencies do not form, verify AS number (100), matching K-values (defaults), and correct network statements on each transit /30
• If routes are missing, confirm no auto-summary is set and the advertising interface is included by the network command
• If path preference is not as intended, compare interface delay values and recalculate cumulative path delay; ensure only R1’s Eth0/1 delay is raised
• Use show ip eigrp neighbors to ensure all three adjacencies are up and stable
• Use show interfaces on R1 Eth0/1 to verify DLY reflects the configured tuning (delay 2000)