State | The communication state for two adjacent routers: |
| Down: This is the initial state of a neighbor conversation. It indicates that there |
| has been no recent information received from the neighbor. |
| Attempt: This state is only valid for neighbors attached to |
| networks. It indicates that no recent information has been received from the |
| neighbor, but that the router is attempting to contact the neighbor by sending |
| Hello packets. |
| Init: A Hello packet has recently been seen from the neighbor. However, |
| bidirectional communication has not yet been established with the neighbor. |
| |
| the most advanced state short of beginning adjacency establishment. Note that |
| both the Designated Router and Backup Designated Router are selected from |
| the set of neighbors in state |
| ExStart: This is the first step in creating an adjacency between the two |
| neighboring routers. The goal of this step is to decide which router is the master, |
| and to decide upon the initial sequence number. Neighbor conversations in this |
| state or greater are called adjacencies. |
| Exchange: The router is describing its entire link state database by sending |
| database description packets to the neighbor. (Each database description |
| packet has a sequence number, and is explicitly acknowledged.) All adjacencies |
| in Exchange state or greater are used by the flooding procedure. In fact, these |
| adjacencies are fully capable of transmitting and receiving all types of OSPF |
| routing protocol packets. |
| Loading: Link State Request packets are sent to the neighbor asking for more |
| recent advertisements that have been discovered (but not yet received) in the |
| Exchange state. |
| Full: The neighboring routers are fully adjacent. These adjacencies will now |
| appear in router links and network links advertisements. |
Events | The number of events encountered that cause a neighbor state change since |
| boot up. |
|
|
WGS3 Layer 3 Switch User’s Manual | - 127 - |