ISIS_1.3.6.1.3.37.2.0.12 isisAreaMismatch

Description

ISIS/3/AREA_MISMATCH:OID [oid] IS-IS received a level-1 Hello PDU whose area address is different from the local area address. (sysInstance=[integer], sysInstanceofLevel=[integer], sysLevel=[integer], sysInstanceofCircIfIndex=[integer], circIndex=[integer], ifIndex=[integer], circIfIndex=[integer], pduFragment=[opaque], ifName=[string])

The area address of the received Level-1 Hello packet was different from that of the local Level-1 IS-IS.

Attribute

Alarm ID	Alarm Severity	Alarm Type
1.3.6.1.3.37.2.0.12	Minor	environmentalAlarm(6)

Parameters

Name	Meaning
oid	Indicates the MIB object ID of the alarm.
sysInstance	Indicates the ID of the IS-IS process.
sysInstanceofLevel	Indicates the ID of the IS-IS process.
sysLevel	Indicates the IS-IS level: 1: Level-1 2: Level-2
sysInstanceofCircIfIndex	Indicates the ID of the IS-IS process.
circIndex	Indicates the index of the interface.
ifIndex	Indicates the index of the interface.
circIfIndex	Indicates the IF index of the interface.
pduFragment	Indicates the fragment of 64-byte PDU header.
ifName	Indicates the name of the interface.

Impact on the System

1. If the trap is triggered because of a hardware fault of the board, route flapping may occur and the CPU usage will increase.

2. If the trap is triggered because of incorrect configuration, neighbors cannot be established, and routes cannot be learnt from each other.

Possible Causes

1. The configuration was incorrect.

2. The area address field was modified.

Procedure

Based on the IS-IS packet format defined in ISO10589, search for the pdu-fragment field (in hexadecimal) in the trap and fetch the system ID of the source switch. Then, run the display this command in the IS-IS view to check whether the area address configured on the source switch is the same as that of the local switch.

If so, go to Step 3.
If not, go to Step 2.

**Table 1** Methods of searching for system IDs and types of IS-IS packets
Searching for the Packet Type	Searching for the System ID
Hello: the 5th byte in the pdu-fragment field being 0f, 10, or 11	The system ID is continuous 6 bytes after the 10th byte in the pdu-fragment field
LSP: the 5th byte in the pdu-fragment field being 12 or 14	The system ID is continuous 6 bytes after the 13th byte in the pdu-fragment field
SNP: the 5th byte in the pdu-fragment field being 18, 19, 1A, or 1B	The system ID is continuous 6 bytes after the 11th byte in the pdu-fragment field

Run the network-entity command in the IS-IS view of the source switch to configure a new IS-IS area address so that the area address of the switch is consistent with that of the local switch. Then, check whether the trap is cleared.
- If so, go to Step 4.
- If not, go to Step 3.
Collect the trap information, log information, and configuration of the switch, and contact technical support personnel.
End.

Related Information

None