So, in order for the global routing table to have EIGRP routes in it, EIGRP has to first be enabled, then go through a process through with it determines which routes are Feasible successors (Best routes) and only then install them to the global routing table.
EIGRP has five basic messages it uses for this EIGRP collaboration between its neighbors.
- Hello
- Update
- Query
- Reply
- ACK