EIGRP establishing remote neighbors

EIGRP is able to establish neighbor adjacencies between EIGRP routers that are not directly connected. This feature is known as EIGRP Over the Top. This can be configured in two ways:

By using the remote-neighbors command. This command is used to enable an EIGRP router to become remote neighbors by accepting inbound connections from any remote IP address. This command includes configuration parameters such as:

  • the use of multicast or unicast
  • can accept connections without manually configuring the remote neighbor IP address
  • can encapsulate neighbor route data within LISP
  • can specify from which remote IP addresses EIGRP neighborships will be accepted
  • can specify the maximum number of neighbors.

Alternatively, the remote keyword can be used at the end of a neighbor statement in the EIGRP configuration mode, such as in the following example:

neighbor Ethernet0/0 remote 100

This is related to the previous command, but functions differently. The neighbor command must specify the IP address of the neighbor in question. You can use the remote keyword to indicate that the neighbor is not in the same subnet as the local interface.

These commands were introduced in Cisco’s IOS XE release 3.10S, and they were actually incorporated into IOS release 15.3(3)S.