ISIS_1.3.6.1.3.37.2.0.17 isisAdjacencyChange

Trap Buffer Description

ISIS adjacency state change. (SysInstance=[IsisSysInstance], SysLevel=[IsisSysLevelIndex], CircIndex=[IsisCircIndex], CircIfIndex=[IsisCircIfIndex], LspId=[IsisPduLspId], AdjState=[IsisAdjState], IfIndex=[IfIndex], IfName=[IfName], Reason=[HwIsisAdjChgReason], SubReason=[HwIsisAdjChgSubReason])

The IS-IS adjacency state changed.

Trap Attributes

Trap Attribute	Description
Alarm or Event	Alarm
Trap Severity	Critical
Mnemonic Code	isisAdjacencyChange
Trap OID	1.3.6.1.3.37.2.0.17
MIB	ISIS-MIB
Alarm ID	0x0001009e
Alarm Name	isisAdjacencyChange
Alarm Type	communicationsAlarm
Raise or Clear	Raise
Match trap	-

Trap Buffer Parameters

Parameter	Description
IsisSysInstance	Indicates the IS-IS process ID.
IsisSysLevelIndex	Indicates the type of the IS-IS neighbor.
IsisCircIndex	Indicates the interface index in the IS-IS process.
IsisCircIfIndex	Indicates the interface index.
IsisPduLspId	Specifies the LSP ID.
IsisAdjState	Indicates the status of a neighbor. 1:Down 2:Init 3:Up 4:Fail
IfIndex	Indicates the interface IF index.
IfName	Indicates the interface name.
HwIsisAdjChgReason	Reason for the status change of the IS-IS adjacency. When the Reason parameter is The alarm was cleared, the trap indicates that an alarm has been cleared. The other values of the Reason parameter indicate that an alarm has been generated.
HwIsisAdjChgSubReason	Indicates the detailed reason why the neighbor status changes. 1: Adjacency state go to Up 2: Delete adjacency 3: Delete interface 4: Interface silent 5: Received invalid hello packet 6: Hello packet authentication failed 7: SystemID in hello conflict with local or different with adj 8: Maximum area number mismatch with local 9: Area Mismatch 10: Adjacency HoldTimer Expired 11: Interface state go to down

VB Parameters

VB OID	VB Name	VB Index
1.3.6.1.3.37.1.1.1.1.1	isisSysInstance	isisSysInstance
1.3.6.1.3.37.1.2.1.1.1	isisSysLevelIndex	isisSysInstance isisSysLevelIndex
1.3.6.1.3.37.1.3.1.1.2	isisCircIfIndex	isisSysInstance isisCircIndex
1.3.6.1.3.37.1.10.1.1.1	isisPduLspId	isisSysInstance
1.3.6.1.3.37.1.10.1.1.9	isisAdjState	isisSysInstance

Impact on the System

IS-IS may re-calculate routes, which causes route flapping and interrupts the IS-IS service.

Possible Causes

Cause 1: The adjacency HoldTimer expired
Cause 2: The physical interface went Down
Cause 3: Protocol reason
Cause 4: BFD detected that the neighbor went Down
Cause 5: Configurations changed
Cause 6: Peer router reason

Procedure

Cause 1: The adjacency HoldTimer expired
1. Run the ping command to check whether the link to the peer device is in the normal state.
- If so, go to step 2.
- If no, go to Step 4.
2. Run the display current-configuration configuration isis command to check whether the IS-IS configuration on the peer device is correct.
- If yes, go to Step 3.
- If no, go to Step 5.
3. Run the display cpu-usage command to check whether the CPU usage is too high.
- If yes, go to step 6.
- If no, go to Step 7.
4. Check the link configuration and go to step 7.

5. Modify the configuration according to the IS-IS protocol and check whether the neighbor status is Up.
- If yes, go to step 8.
- If no, go to Step 7.
6. Run the display current-configuration command to check the device configuration. Delete unnecessary configurations and check whether the neighbor status is Up.
- If yes, go to step 8.
- If no, go to Step 7.
7. Collect alarm and configuration information, and contact technical support personnel.

8. End.
Cause 2: The physical interface went Down
1. Run the display isis interface command to check whether the interface status is Down.
- If so, go to step 2.
- If not, go to step 3.
2. Modify the configuration and check whether the interface status changes to Up.
- If yes, go to Step 4.
- If not, go to step 3.
3. Collect alarm and configuration information, and contact technical support personnel.

4. End.
Cause 3: Protocol reason
1. Run the display current-configuration command to check whether the local configurations are correct.
- If so, go to step 3.
- If not, go to step 2.
2. Modify the local configurations, and then check whether the neighbor goes Up.
- If so, go to step 6.
- If not, go to step 5.
3. Run the display cpu-usage command to check whether the CPU usage is overhigh.
- If so, go to step 4.
- If not, go to step 5.
4. Delete unnecessary configurations, and then check whether the neighbor is Up.
- If so, go to step 6.
- If not, go to step 5.
5. Collect alarm information and configuration information, and then contact technical support personnel.

6. End.
Cause 4: BFD detected that the neighbor went Down
1. Run the ping command to check whether the link to the peer device is in the normal state.
- If yes, go to Step 3.
- If not, go to step 2.
2. Check the link configuration.

3. Collect alarm and configuration information, and contact technical support personnel.

4. End.
Cause 5: Configurations changed
1. Check whether a modified configuration affects the neighbor relationship establishment.
- If so, go to step 2.
- If not, go to step 4.
2. Check whether the configuration modification is expected.
- If so, go to step 5.
- If not, go to step 3.
3. Restore the configurations, and then check whether the neighbor is Up.
- If so, go to step 5.
- If not, go to step 4.
4. Collect alarm information and configuration information, and then contact technical support personnel.

5. End.
Cause 6: Peer router reason
1. Check whether the configuration on the remote device is correct.
- If so, go to step 2.
- If not, go to step 3.
2. Rectify the fault on the peer device and check whether the neighbor relationship is Up.
- If yes, go to Step 4.
- If not, go to step 3.
3. Collect alarm and configuration information, and contact technical support personnel.

4. End.