LevelOne GSW-2600TXM manual 168

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.

Displaying the Virtual Neighbor Table

Virtual links can be used to link an area isolated from the backbone, to create a redundant link between any area and the backbone to help prevent partitioning, or to connect two existing backbone areas into a common backbone. Note that the processes of establishing a active link between virtual neighbors is similar to that used for physically adjacent neighbors.

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