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 non-broadcast

 

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.

 

2-Way: Communication between the two routers has been established. This is

 

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 2-Way or greater.

 

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

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