show ip ospf neighbor

Displays OSPF neighbor information.

Syntax

show ip ospf neighbor [ extensive | num | router-id A.B.C.D ]

Parameters

extensive
Displays detailed neighbor information.
num
Specifies displays only the entry in the specified index position in the neighbor table. For example, if you enter "1", only the first entry in the table is displayed.
router-id A.B.C.D
Displays neighbor information for the specified router ID.

Modes

User EXEC mode

Usage Guidelines

Command Output

The show ip ospf neighbor command displays the following information:

Output field

Description

Port

The port through which the device is connected to the neighbor.

Address

The IP address of the port on which this device is connected to the neighbor.

Pri

The OSPF priority of the neighbor.

  • For multi-access networks, the priority is used during election of the Designated Router (DR) and Backup designated Router (BDR).
  • For point-to-point links, this field shows one of the following values:
  • 1 = point-to-point link
  • 3 = point-to-point link with assigned subnet

State

The state of the conversation between the device and the neighbor. This field can have one of the following values:

  • Down - The initial state of a neighbor conversation. This value 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.
  • Init - A Hello packet has recently been seen from the neighbor. However, bidirectional communication has not yet been established with the neighbor. (The router 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.
  • 2-Way - Communication between the two routers is bidirectional. This is the most advanced state before beginning adjacency establishment. The Designated Router and Backup Designated Router are selected from the set of neighbors in the 2-Way 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 router is describing its entire link state database by sending Database Description packets to the neighbor. Each Database Description packet has a DD sequence number, and is explicitly acknowledged. Only one Database Description 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.

Neigh Address

The IP address of the neighbor.

For point-to-point links, the value is as follows:

  • If the Pri field is "1", this value is the IP address of the neighbor router’s interface.
  • If the Pri field is "3", this is the subnet IP address of the neighbor router’s interface.

Neigh ID

The neighbor router’s ID.

Ev

The number of times the neighbor’s state changed.

Opt

The sum of the option bits in the Options field of the Hello packet. This information is used by Ruckus technical support. Refer to Section A.2 in RFC 2178 for information about the Options field in Hello packets.

Cnt

The number of LSAs that were retransmitted.

Examples

The following example displays information about OSPF neighbors.

device> show ip ospf neighbor 

Port  Address       Pri  State     Neigh Address  Neigh ID    Ev Op Cnt 
v10   10.1.10.1     1    FULL/DR   10.1.10.2      10.65.12.1   5  2  0
v11   10.1.11.1     1    FULL/DR   10.1.11.2      10.65.12.1   5  2  0
v12   10.1.12.1     1    FULL/DR   10.1.12.2      10.65.12.1   5  2  0
v13   10.1.13.1     1    FULL/DR   10.1.13.2      10.65.12.1   5  2  0
v14   10.1.14.1     1    FULL/DR   10.1.14.2      10.65.12.1   5  2  0

History