Contents

1   Introduction

This instruction concerns alarm handling.

1.1   Alarm Description

The alarm is raised when the number of messages that are discarded because of congestion at the Diameter transport layer exceeds a configured threshold value in a given time interval.

The possible alarm causes and fault locations are explained in Table 1.

Table 1    Alarm Causes

Alarm Cause	Description	Fault Reason	Fault Location	Impact
Too high traffic at Diameter transport layer	The number of messages that get discarded because of congestion exceeds a configured threshold value in a given time interval	Congestion at Diameter transport layer	Transport layer – SCTP or TCP	Message loss

The alarm attributes are listed and explained in Table 2.

Table 2    Alarm Attributes

Attribute Name	Attribute Value
Major Type	193
Minor Type	2250572781
Managed Object Class	DIA-CFG-Conn
Managed Object Instance	ManagedElement=<node_name>,<ManagedFunction>=<FunctionId>,DIA-CFG-Application=DIA,DIA-CFG-StackContainer=<stackId>,DIA-CFG-PeerNodeContainer=<stackId>,DIA-CFG-NeighbourNode=<hostId>#<stackId>,DIA-CFG-Conn=<stackId>#<hostId>#<connId>
Specific Problem	vDicos, Diameter Link Congested
Event Type	communicationsAlarm (2)
Probable Cause	x733ThresholdCrossed (351)
Additional Text	Diameter Link Congested
Perceived Severity	minor (5)

1.2   Prerequisites

This section provides information on the documents, tools, and conditions that apply to the procedure.

1.2.1   Documents

This instruction references the following document:

• Data Collection Guideline

1.2.2   Tools

No tools are required.

1.2.3   Conditions

Before starting this procedure, ensure that the following conditions are met:

• A vDicos, Diameter Link Congested alarm is raised.
• System authorization and authentication have passed successfully.
• Diameter configuration data is correctly defined.

2   Procedure

This section describes the procedure to follow when this alarm is received.

2.1   Analyzing Alarm

In the following cases, alarms must not be cleared manually by the user; they are cleared automatically:

• The observed measurement value is lower than the low threshold of the smallest non-empty severity.
• No measurement result is available during the granularity period.
• The threshold reader is deleted or disabled.
• The threshold monitor is deleted or disabled.

2.2   Procedure

Do the following:

1. Wait up to 5 minutes for the alarm to be cleared automatically. The time depends on the alarm configuration, traffic rate over the link, and the network bandwidth.
2. Is the alarm cleared?

   Yes: Proceed with Step 9.

   No: Continue with the next step.

3. Are the thresholds and the granularity period for the corresponding alarm set correctly?

   Yes: Proceed with Step 6.

   No: Continue with the next step.

4. Set appropriate values for attributes thresholdHigh and thresholdLow of the relevant PmThresholdMonitoring Managed Object (MO), and granularityPeriod of the PmJob MO for the alarm.
5. Wait for the alarm to be cleared automatically after elapsing of two granularity periods.
6. Is the alarm cleared?

   Yes: Proceed with Step 9.

   No: Continue with the next step.

7. Perform data collection, refer to Data Collection Guideline.
8. Consult the next level of maintenance support. Further actions are outside the scope of this instruction.
9. Job is completed.