CCNP Routing and Switching TSHOOT 300-135: Official Cert Guide

Chapter 15

Table 15-2 Adjacency States

State	Description
Down	This state indicates that no hellos have been received from a neighbor.
Attempt	This state occurs after a router sends a unicast hello (as opposed to a multicast hello) to a configured neighbor and has not yet received a hello from that neighbor.
Init	This state occurs on a router that has received a hello message from its neighbor; however, the OSPF RID of the receiving router was not contained in the hello message. If a router remains in this state for a long period, something is probably preventing that router from correctly receiving hello packets from the neighboring router.
2Way	This state occurs when two OSPF routers receive hello messages ...