Interface model suppressed in Spectrum even though configured to generate an alarm

Products

• Network Observability
• Spectrum

Issue/Introduction

We have modeled a connection between tow devices models.

The interface on one side of the connection has alarming disabled by setting the GeneratePortStatusAlarms attribute id 0x12a54 to No.

The other interface is configured to alarm by setting the GeneratePortStatusAlarms attribute id 0x12a54 to Yes and the ok_to_poll attribute id 0x11dd8 to yes.

When the link went down, we did not get an alarm on the interface where alarming was disabled, however, on the interface that was configured to alarm, instead of getting the expected Critical "BAD LINK DETECTED" alarm, the interface was Suppressed with the following event:

Suppressed

Jun 3, 2024, 7:56:40 AM EDT

Device_Hu1/0/28

The bad link status of port (name - Device_1/0/28, type - Gen_IF_Port) has been suppressed because its linked interface, or linked interface's device, is DOWN.

System

0x10d18

Jun 3, 2024, 3:11:40 PM EDT

System

Gen_IF_Port

10

 

Environment

Version: Any
Component: Alarms and Events

Cause

Even though alarming is disabled on the one interface, the AlarmOnLinkDownTrap attribute id 0x11fc2 is set to 1 (Check Status) by default.

So what is happening is Spectrum is receiving a Link Down trap for that interface. So Spectrum sets that interface to down but because you are not alarming on that interface but the condition stays Green/Normal.

The other interface also goes down. This has alarming enabled. Instead of going Red/Critical, Spectrum says the connected port is down so it turn this interface Suppressed with the event noted above.

Resolution

This is functioning as designed.

To get the expected Critical alarm in this instance, set the AlarmOnLinkDownTrap attribute id 0x11fc2 to  Never (0) on the interface you do not wish to alarm on. Then when this happens again, the interface will alarm Red/Critical with the "BAD LINK DETECTED".