ISIS_1.3.6.1.3.37.2.0.4 isisAttemptToExceedMaxSequence

Description

ISIS/3/MAXSEQ_EXCEED:OID [oid] The LSP sequence number almost reaches the maximum value. (sysInstance=[integer], sysInstanceofLevel=[integer], sysLevel=[integer], pduLspId=[opaque])

The sequence number of the IS-IS LSP would reach the maximum value.

Attribute

Alarm ID	Alarm Severity	Alarm Type
1.3.6.1.3.37.2.0.4	Minor	other(1)

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
pduLspId	Indicates the LSP ID.

Impact on the System

After the sequence number reaches the maximum value 0xFFFFFFFF, the IS-IS process will be suspended for a period of time, namely, the sum of the maximum lifetime and zero aging time of an LSP. As a result, IS-IS services will be interrupted.

Possible Causes

The sequence number of the LSP generated locally reached the maximum value 0xFFFFFFFF.

Procedure

If the trap is automatically cleared, no action is required. If the trap persists, after the LSP whose sequence number is 0xFFFFFFFF (the maximum lifetime of an LSP + 60, of which, the default maximum lifetime of an LSP is 1200s) ages out, the sequence number of the LSP starts from 1 again. The display isis lsdb local command can be used to check the Seq Num field of an LSP generated by the local switch.
- If the increasing speed of the LSP sequence number is matched with the configured refreshing period, it indicates that this trap message is informational only, and no action is required, go to Step 5.
- If the sequence number increases quickly, go to Step 2.
Check whether there is another switch whose system ID is the same as the system ID or the virtual system ID of the local switch. According to ISO10589, the system ID in an IS-IS domain must be unique.
- If so, go to Step 3.
- If not, go to Step 4.
Enter the IS-IS view of the local switch or another switch whose system ID is the same as the system ID or the virtual System ID of the local switch. Then run the undo network-entity command or the undo virtual-system command to delete the repeated system ID or virtual system ID and the network-entity command or the virtual-system command to configure a different system ID or virtual system ID for the switch. Check whether the trap is cleared. If the undo network-entity or undo virtual-system command is run, the conflicting system ID or virtual system ID becomes unavailable. Therefore, make sure that the system ID or virtual system ID conflict exists before you run the undo network-entity or undo virtual-system command.
- If so, go to Step 5.
- If not, go to Step 4.
Collect the trap information, log information, and configuration of the switch, and contact technical support personnel.
End.

Related Information

None