Field
Description
State
The state of the conversation (the adjacency) between your routing switch
and the neighbor. The possible values are:
INIT
A Hello packet has recently been seen from the neighbor. However,
bidirectional communication has not yet been established with the
neighbor. (The switch itself did not appear in the neighbor's hello
packet.) All neighbors in this state (or higher) are listed in the hello
packets sent from the associated interface.
2WAY
Communication between the two routers is bidirectional. This is the
most advanced state before beginning adjacency establishment. The
DR and BDR are selected from the set of neighbors in the 2Way state
or greater.
EXSTART
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 database description (DD) sequence
number. Neighbor conversations in this state or greater are called
adjacencies.
EXCHANGE
The switch is describing its entire link state database by sending DD
packets to the neighbor. Each DD packet has a DD sequence number
and is explicitly acknowledged. Only one DD packet can be outstanding
at any time. In this state, link-state request packets can also be sent
asking for the neighbor's more recent advertisements. 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 the 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 link advertisements.
Rxmt QLen
Remote transmit queue length—The number of LSAs that the routing
switch has sent to this neighbor and for which the routing switch is
awaiting acknowledgements.
Events
The number of times the neighbor's state has changed.
Table Continued
Chapter 11 Open Shortest Path First Protocol (OSPF)
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