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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.
Note:
To scroll through the table, use the <Next Page> and <Prev Page> buttons. To
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<Apply>.
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