OcNOS-RON : Layer 3 Guide : Open Shortest Path First Command Reference : OSPFv2 Commands : show ip ospf neighbor
show ip ospf neighbor
Use this command to display information about OSPF neighbors.
Command Syntax
show ip ospf (<0-65535>|) neighbor
show ip ospf (<0-65535>|) neighbor all
show ip ospf (<0-65535>|) neighbor interface A.B.C.D
show ip ospf (<0-65535>|) neighbor A.B.C.D
show ip ospf (<0-65535>|) neighbor A.B.C.D detail
show ip ospf (<0-65535>|) neighbor detail
show ip ospf (<0-65535>|) neighbor detail all
Parameters
<0-65535>
The ID of the router process
all
Include downstatus neighbor
A.B.C.D
IPv4 address
detail
Details of neighbors
Command Mode
Privileged Exec mode and Exec mode
Applicability
This command was introduced before OcNOS version 1.3.
Example
#show ip ospf neighbor
 
Total number of full neighbors: 3
OSPF process 1 VRF(default):
Neighbor ID Pri State Dead Time Address Interface Instance ID
1.1.1.1 1 Full/ - inactive 14.1.1.1 p7p1 0
3.3.3.3 1 Full/ - 00:01:41 15.1.1.2 p8p1 0
3.3.3.3 1 Full/ - inactive 15.1.1.2 VLINK0
OSPF Neighbor Fields
Table 1-19 explains the fields for each neighbor entry.
 
Table 1-19: OSPF neighbor output details
Field
Description
OSPF process
OSPF process identifier.
Neighbor ID
OSPF router identifier of the neighbor.
Pri
OSPF priority of the neighbor.
State
State of the OSPF neighbor:
 
DependUpon: dummy state
 
Down: no OSPF neighbors detected at this instant
 
Attempt: in an NBMA environment, the router sends unicast hello packets every poll interval to the neighbor, from which hellos have not been received within the dead interval
 
Init: hello packet received, but the receiving router's ID was not included in the hello packet
 
2-Way: bi-directional communication established between two routers
 
ExStart: master and slave roles determined
 
Exchange: database description packets (DBD) sent
 
Loading: exchange of LSRs (link state request) and LSUs (link state update) packets
 
Full: routers fully adjacent with each other.
Dead Time
If a new Hello is not received within this duration, the neighbor is declared dead.
Address
IP address of neighbor’s interface attached to the network.
Interface
The interface attached to the network on which the neighbor is located.
Instance ID
Instance identifier for the session.
Example: Detail Parameter
This is sample output from the command when the detail parameter is specified:
#show ip ospf neighbor detail
Neighbor 10.10.10.50, interface address 10.10.10.50
In the area 0.0.0.0 via interface eth0
Neighbor priority is 1, State is Full, 5 state changes
DR is 10.10.10.50, BDR is 10.10.10.10
Options is 0x42 (*|O|-|-|-|-|E|-)
Dead timer due in 00:00:38
Neighbor is up for 00:53:07
Database Summary List 0
Link State Request List 0
Link State Retransmission List 0
Crypt Sequence Number is 0
Thread Inactivity Timer on
Thread Database Description Retransmission off
OSPF Neighbor Detail Fields
Table 1-20 explains the fields for each neighbor detail entry.
 
Table 1-20: OSPF neighbor output detail 
Field
Description
Neighbor
OSPF router identifier of the neighbor.
interface address
IP address of the neighbor interface.
In the area
Area and interface through which the OSPF neighbor is known.
Neighbor priority
OSPF priority of the neighbor.
State
OSPF state as explained in Table 1-19.
state changes
Number of state changes since the neighbor was created.
Hello is suppressed
Hello suppression is enabled.
Poll interval
Poll timer value.
DR is
Router ID of the designated router for the interface.
BDR is
Router ID of the backup designated router for the interface.
Options
LSA options as explained in Table 1-9.
LLS Options
LSDB Resynchronization (LR)
Restart Signal (RS-bit)
Whether link-local signalling (LLS) and out-of-band (OOB) link-state database resynchronization are performed for nonstop forwarding (NSF).
OOB-Resync in progress (receiver)/last OOB-Resync
Last successful OOB resynchronization with the NSF-capable neighbor. The router waits before taking a neighbor adjacency down if the OOB resynchronization has not taken place since the time a restart signal (Hello packet with RS-bit set) was received from the neighbor.
Dead timer due in
Expected time before declaring the neighbor dead.
Poll due in
Poll timer thread.
Neighbor is up for
Time since the neighbor went into the two-way state.
Database Summary List
Number of LSAs in the neighbor’s database.
Link State Request List
Number of LSAs that need to be received from this neighbor to synchronize the neighbors' topological databases.
Link State Retransmission List
Number of advertisements flooded out an adjacency. To ensure flooding is reliable, advertisements are retransmitted until they are acknowledged.
Crypt Sequence Number is
MD5 cryptographic sequence number.
Thread Inactivity Timer
Off if hello suppression is enabled, on otherwise.
Thread Database Description Retransmission
Off if hello suppression is enabled, on otherwise.
Thread Link State Request Retransmission
Off if hello suppression is enabled, on otherwise.
Thread Link State Update Retransmission
Off if hello suppression is enabled, on otherwise.
Thread Poll Timer
Whether the poll timer thread is on.
Bidirectional Forwarding Detection is enabled
Status of BFD, enabled or disabled.
Example: Hello-Suppression Option
This is sample output from the command when the detail parameter is specified and Hello-Suppression is enabled:
#sh ip os neighbor detail
Neighbor 1.1.1.1, interface address 14.1.1.1
In the area 0.0.0.0 via interface p7p1
Neighbor priority is 1, State is Full, 5 state changes
Hello is suppressed
DR is 0.0.0.0, BDR is 0.0.0.0
Options is 0x62 (-|O|DC|-|-|-|E|-)
Dead timer due in inactive
Neighbor is up for 00:05:03
Database Summary List 0
Link State Request List 0
Link State Retransmission List 0
Crypt Sequence Number is 0
Thread Inactivity Timer off
Thread Database Description Retransmission off
Thread Link State Request Retransmission off
Thread Link State Update Retransmission off
 
Last modified date: 08/28/2023