EIGRP - Routing Protocols and Concepts - page 405

B1 EIGRP routing configuration:
B1(config)# router eigrp 1
B1(config-router)# network 172.16.1.32 0.0.0.3
B1(config-router)# network 10.10.8.0 0.0.3.255

B2 EIGRP routing configuration:
B2(config)# router eigrp 1
B2(config-router)# network 172.16.1.36 0.0.0.3
B2(config-router)# network 10.10.12.0 0.0.1.255

B3 EIGRP routing configuration:
B3(config)# router eigrp 1
B3(config-router)# network 172.16.1.40 0.0.0.3
B3(config-router)# network 10.10.14.0 0.0.0.255

In addition to the network commands for each router, disable unnecessary EIGRP packets from being
sent out interfaces that do not have an EIGRP neighbor. For example, HQ should neither send EIGRP
Hello packets to ISP nor to the two LANs.

What command will disable unnecessary EIGRP packets from being sent out an interface? (Hint: The
command for RIP is exactly the same.)
Router(config-route)# passive-interface interface

By default, EIGRP automatically summarizes routes at the major network boundary. Because the
topology is discontiguous, you must disable this automatic summarization with the no auto-summary
command, just as you did in RIPv2.

Verifying EIGRP

Before any updates can be sent or received by EIGRP, routers must establish adjacencies with their
neighbors. EIGRP routers establish adjacencies with neighbor routers by exchanging EIGRP Hello
packets.

Use the show ip eigrp neighbors command to view the neighbor table and verify that EIGRP has
established an adjacency with its neighbors. This command is useful for verifying and troubleshooting
EIGRP. Example 9-1 shows the neighbor table for HQ.

Example 9-1 EIGRP Neighbor Table for HQ

HQ# show ip eigrp neighbors
IP-EIGRP neighbors for process 1
H Address Interface Hold Uptime SRTT RTO Q Seq
(sec) (ms) Cnt Num
0 172.16.1.38 Ser0/1/0 14 00:01:15 40 500 0 17
1 172.16.1.42 Ser0/1/1 14 00:01:15 40 500 0 17
2 172.16.1.34 Ser0/0/1 14 00:01:15 40 500 0 17