CCNA3 - Lab 5.4.2.4 EIGRP Configuring Automatic and Manual Route Summarization and Discontiguous Subnets

Step 1: Connect the equipment

1. Connect Router1 to Router2 and Router3 using serial cables.
2. Connect Router2 to Router3 using serial cables.
3. Connect a PC with a console cable to perform configurations on the routers.

Step 2: Perform basic configurations on the routers

1. Establish a console session with Router1 and configure hostname, passwords, and interfaces as described in the table. Save the configuration.
2. Establish a console session with Router2 and perform a similar configuration, using the addresses and other information from the table. Save the configuration.
3. Establish a console session with Router3. Configure hostname, passwords, and interfaces according to the table. Save the configuration.

Step 3: Configure EIGRP routing with default commands

1. On Gateway, configure EIGRP as the routing protocol with an autonomous system number of 100, and advertise the appropriate networks.
2. On Branch1, configure EIGRP as the routing protocol with an autonomous system number of 100, and advertise the appropriate networks:
3. Perform a similar configuration on Branch2, using EIGRP 100 and advertising the appropriate networks.

Step 4: Verify the routing configuration

1. View the routing table on Gateway.
2. Which subnets are not reported in this output? Jawaban: The subnets configured for the 172.16.0.0 and 172.17.0.0 networks are absent.
3. Why are there two paths reported for the 10.0.0.8/30 route? Jawaban: Because no bandwidth commands have been configured, EIGRP has two equal-cost paths to report.

Step 5: Remove Automatic summarization

On each of the three routers, remove automatic summarization to force EIGRP to report all subnets. A sample command is given for Gateway.

Step 6: Verify the routing configuration

View the routing table again on Gateway.

Step 7: Configure manual summarization

On Branch2, configure manual summarization to force EIGRP to summarize only the 172.17.0.0 subnets.

Step 8: Reflection

1. Although removing automatic summarization solved the issue of missing subnets, what possible problem could it cause? Jawaban: The routing table is very long, and that will slow down the lookup process.
2. How could removing automatic summarization help in troubleshooting an EIGRP network? Jawaban: Checking the output against all possible subnets will reveal which subnet(s) are missing. Those are the connections and configurations that need to be checked.