Similar to EIGRP for IPv4, before any EIGRP for IPv6 updates can be sent or received, routers must establish adjacencies with their neighbors, as shown in Figure 1.

Use the show ipv6 eigrp neighbors command to view the neighbor table and verify that EIGRP for IPv6 has established an adjacency with its neighbors. The output shown in Figure 2 displays the IPv6 link-local address of the adjacent neighbor and the interface that this router uses to reach that EIGRP neighbor. Using meaningful link-local addresses makes it easy to recognize the neighbors R2 at FE80::2 and R3 at FE80::3.

The output from the show ipv6 eigrp neighbors command includes:

The show ipv6 eigrp neighbors command is useful for verifying and troubleshooting EIGRP for IPv6. If an expected neighbor is not listed, ensure that both ends of the link are up/up using the show ipv6 interface brief command. The same requirements exist for establishing neighbor adjacencies with EIGRP for IPv6 as it does for IPv4. If both sides of the link have active interfaces, check to see: