TP-Link T3700G-28TQ T3700G-28TQ V1 UG - Page 208

Link State Database, State, Events, Retransmission, Queue length, Dead Time

Page 208 highlights

State: Events: Retransmission Queue length: Dead Time: The state of the neighbor:  Down: This is the initial state of a neighbor conversation. It indicates that there has been no recent information received from the neighbor. On NBMA networks, Hello packets may still be sent to 'Down' neighbors, although at a reduced frequency.  Attempt: This state is only valid for neighbors attached to NBMA networks. It indicates that no recent information has been received from the neighbor, but that a more concerted effort should be made to contact the neighbor. This is done by sending the neighbor Hello packets at intervals of Hello Interval.  Init: In this state, a Hello packet has recently been seen from the neighbor. However, bidirectional communication has not yet been established with the neighbor (i.e., the router itself did not appear in the neighbor's Hello packet). All neighbors in this state (or greater) are listed in the Hello packets sent from the associated interface.  2-Way: In this state, communication between the two routers is bidirectional. This has been assured by the operation of the Hello Protocol. This is the most advanced state short of beginning adjacency establishment. The (Backup) Designated Router is 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 DD sequence number. Neighbor conversations in this state or greater are called adjacencies.  Exchange: In this state the router is describing its entire link state database by sending Database Description packets to the neighbor. In this state, Link State Request Packets may also be sent asking for the neighbor's more recent LSAs. All adjacencies in Exchange state or greater are used by the flooding procedure. These adjacencies are fully capable of transmitting and receiving all types of OSPF routing protocol packets.  Loading: In this state, Link State Request packets are sent to the neighbor asking for the more recent LSAs that have been discovered (but not yet received) in the Exchange state.  Full: In this state, the neighboring routers are fully adjacent. These adjacencies will now appear in Router LSAs and Network LSAs. The number of times this neighbor relationship has changed state, or an error has occurred. An integer representing the current length of the retransmission queue of the specified neighbor router ID of the specified interface. The amount of time, in seconds, to wait before the router assumes the neighbor is unreachable. 10.9.11 Link State Database Choose the menu Routing→OSPF→Link State Database to load the following page. 197

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State:
The state of the neighbor:
Down: This is the initial state of a neighbor conversation.
It indicates that there has been no recent information
received from the neighbor. On NBMA networks, Hello
packets may still be sent to 'Down' neighbors, although at
a reduced frequency.
Attempt: This state is only valid for neighbors attached to
NBMA networks. It indicates that no recent information
has been received from the neighbor, but that a more
concerted effort should be made to contact the neighbor.
This is done by sending the neighbor Hello packets at
intervals of Hello Interval.
Init: In this state, a Hello packet has recently been seen
from the neighbor. However, bidirectional communication
has not yet been established with the neighbor (i.e., the
router itself did not appear in the neighbor's Hello packet).
All neighbors in this state (or greater) are listed in the
Hello packets sent from the associated interface.
2-Way: In this state, communication between the two
routers is bidirectional. This has been assured by the
operation of the Hello Protocol. This is the most advanced
state short of beginning adjacency establishment. The
(Backup) Designated Router is 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 DD sequence number. Neighbor conversations
in this state or greater are called adjacencies.
Exchange: In this state the router is describing its entire
link state database by sending Database Description
packets to the neighbor. In this state, Link State Request
Packets may also be sent asking for the neighbor's more
recent LSAs. All adjacencies in Exchange state or greater
are used by the flooding procedure. These adjacencies
are fully capable of transmitting and receiving all types of
OSPF routing protocol packets.
Loading: In this state, Link State Request packets are sent
to the neighbor asking for the more recent LSAs that have
been discovered (but not yet received) in the Exchange
state.
Full: In this state, the neighboring routers are fully
adjacent. These adjacencies will now appear in Router
LSAs and Network LSAs.
Events:
The number of times this neighbor relationship has changed
state, or an error has occurred.
Retransmission
Queue length:
An
integer
representing
the
current
length
of
the
retransmission queue of the specified neighbor router ID of the
specified interface.
Dead Time:
The amount of time, in seconds, to wait before the router
assumes the neighbor is unreachable.
10.9.11 Link State Database
Choose the menu
Routing
OSPF
Link State Database
to load the following page.
197