OSPF_1.3.6.1.2.1.14.16.2.2 ospfNbrStateChange

Description

OSPF/2/NBRCHG:OID [oid] The status of the non-virtual neighbor changes. (NbrIpAddress=[neighbor-ip-address], NbrAddressLessIndex=[neighbor-interface-index], ProcessId=[process-id], AreaId=[area-id], IfnetIndex=[interface-ifnet-index], LocalIfIpAddress=[local-ip-address], ProcessId=[process-id], RouterId=[router-id], NbrRtrId=[neighbor-router-id], NbrState=[neighbor-state], IfName=[interface-name], InstanceName=[instance-name], NbrChgReason=[NbrStateChangeReason])

The status of the OSPF neighbor changed. The possible cause was that the status of the interface of the neighbor changed or the contents of the received Hello packets changed.

Attribute

Alarm ID	Alarm Severity	Alarm Type
1.3.6.1.2.1.14.16.2.2	Major	environmentalAlarm (6)

Parameters

Name	Meaning
oid	Indicates the MIB object ID of the alarm.
NbrIpAddress	Indicates the IP address of the neighbor.
NbrAddressLessIndex	Indicates the index of a neighboring interface.
ProcessId	Indicates the process ID.
AreaId	Indicates the area ID of the NSSA.
IfnetIndex	Indicates the Ifnet index of the interface.
LocalIfIpAddress	Indicates the IP address of the local wireless access controller.
ProcessId	Indicates the process ID.
RouterId	Indicates the router ID of the local wireless access controller.
NbrRtrId	Indicates the router ID of the neighbor.
NbrState	Indicates the status of the neighbor. 1: Down 2: Attempt 3: Init 4: 2Way 5: ExStart 6: Exchange 7: Loading 8: Full
IfName	Indicates the name of interface.
InstanceName	Indicates the instance name.
NbrChgReason	Indicates the reason why the neighbor status changes: 1 (adjacencyHoldTimerExpired): indicates that the timer of the adjacent router times out. 2 (physicalInterfaceChange): indicates that the status of the physical interface on the router changes. 3 (ospfProtocolReason): indicates that an alarm is generated because of the OSPF protocol. 4 (bfdSessionStateChange): indicates that the BFD session is closed. 5 (configureChange): indicates that the OSPF configuration changes. 6 (peerRouterReason): indicates that an alarm is generated because of the neighboring router. 100 (alarmCleared): indicates that the alarm is cleared because services are restored or the neighbor is deleted.

Impact on the System

When the status of the neighbor (not a neighbor of a virtual link) changes, this trap message will be sent. This trap message indicates the status of the neighbor changes. If the neighbor changes from a lower status to a higher status, this trap message is informational only, and no action is required. If the neighbor changes from a higher status to a lower status, services may be interrupted. (The state transition of the OSPF neighbor in an ascending order is: Down -> Init -> 2-way -> Exstart -> Exchange -> Loading -> Full).

On a non-broadcast multi-connection or broadcast network, if the neighbor relationship enters a lower level of state, only the DR generates an ospfNbrStateChange alarm. If the neighbor relationship status change results from an interface down event on the DR, the DR does not generate this alarm but generates an ospfIfStateChange alarm. When the neighbor relationship status becomes stable, the ospfNbrStateChange alarm is cleared only on the DR. If the interface that went down is a non-DR interface, the ospfNbrStateChange alarm may persist.

Possible Causes

1. The status of the interface of the neighbor changed.

2. The configured parameters (such as Hello timer, dead timer, interface authentication, and network type) of the interfaces that set up the neighbor relationship were inconsistent.

3. OSPF was restarted by using the reset ospf process command.

4. An error packet was received.

5. The overflow function is configured and the process entered the Overflow state.

6. The ping operation failed, which indicated that an error occurred during the transmission of the packet.

Procedure

Run the display ospf peer command to check the neighbor status. If the neighbor is in the Full state, go to Step 7; otherwise, go to Step 2.
Run the display ip interface interface-type interface-number command to check whether the interface of the neighbor is in the Down state.
- If the physical interface is Up, go to Step 3.
- If the physical interface is Down, check whether the shutdown command is configured on the interface and the link.
  - If this command is configured, run the undo shutdown command and then go to Step 3.
  - If this command is not configured, go to Step 8.
Check whether the packet is correctly forwarded and ping the IP address of the remote interface.
- If the ping fails, go to Step 7.
- If the ping succeeds, go to Step 4.
Run the display ospf interface interface-type interface-number command to view the state field and check whether the interface where the OSPF neighbor resides is in the Down state.
- If the interface is in the Down state, go to Step 7.
- If the interface is in another state, go to Step 5.
Run the display ospf interface interface-type interface-number command to check whether the configurations (including the hello interval, dead interval, poll interval, and OSPF network-type) on the two ends of the link are consistent and whether the interface on one end is not an OSPF interface.
- If so, go to Step 6.
- If not, modify the configurations to make them consistent. Then check whether the trap is cleared.
  - If so, go to Step 6.
  - If not, run the following commands to modify interface configurations on the two ends to be consistent.
    ospf timer hello interval
    ospf timer dead interval
    ospf timer poll interval
    ospf network-type { broadcast | nbma | p2mp | p2p }
    Then, check whether the trap is cleared.
    If so, go to Step 8.
    
    If not, go to Step 7.
Run the display current-configuration interface interface-type interface-number command to check whether the interface authentication configurations on the two ends are consistent.
- If so, go to Step 7.
- If not, run the following commands to modify interface configurations on the two ends to be consistent.
  - ospf authentication-mode { simple [ plain plain-text | [ cipher ] cipher-text ] | null }
  - ospf authentication-mode { md5 | hmac-md5 | hmac-sha256 } [ key-id { plain plain-text | [ cipher ] cipher-text } ]
  - ospf authentication-mode keychain keychain-name
  Then, check whether the trap is cleared.
  - Y=>8.
  - N=>7.
Collect alarm information and configuration information, and then contact technical support personnel.
End.

Related Information

None