In addition to verifying the autonomous system number, it is necessary to verify that all interfaces are participating in the EIGRP network. The network command that is configured under the EIGRP routing process indicates which router interfaces participates in EIGRP. This command is applied to the classful network address of the interface or to a subnet when the wildcard mask is included.

In Figure 1, the show ip eigrp interfaces command displays which interfaces are enabled for EIGRP on R1. If connected interfaces are not enabled for EIGRP, then neighbors do not form an adjacency.

In Figure 2, the "Routing for Networks" section of the show ip protocols command indicates which networks have been configured; any interfaces in those networks participate in EIGRP.

If the network is not present in this section, use show running-config to ensure that the proper network command was configured.

In Figure 3, the output from the show running-config command confirms that any interfaces with these addresses, or a subnet of these addresses, are enabled for EIGRP.

EIGRP for IPv6

Similar commands and troubleshooting criteria also apply to EIGRP for IPv6.

The following are the equivalent commands used with EIGRP for IPv6: