SNMPC Interface utilization calculation is incorrect and triggering false alarms

Products

• DX Unified Infrastructure Management (Nimsoft / UIM)
• DX Unified Infrastructure Management (Nimsoft / UIM)

Issue/Introduction

Interface utilization data for 20 GB ports are much higher than the actual utilization and triggers false alarms.

Environment

Release : 9.2.0

Component : UIM - SNMPCOLLECTOR

Cause

This is seen when the device's snmp agent does not return the correct ifspeed and ifHighSpeed and causes the Interface Utilization calculation to be incorrect.

Resolution

Solution 1:

Configure the device's snmp agent so the correct ifspeed and ifHighSpeed values are polled.

Solution 2:

Configure the snmpcollector probe Interface Speed Override settings with the correct speed.

 

Additional Information

See the following information in the snmpcollector guide "snmpcollector Known Issues and Workarounds"

Issue:
The interface speed for some virtual interfaces is not reported correctly. The device is not able to detect the true speed of connection for the virtual interface. This issue is seen with WAN-related interfaces.

Workaround:
To calculate utilization on these interfaces, contact your system administrator to determine the maximum speed of the interface. Then set the interface speed in the probe.
The interface speed settings are available with probe v1.42 or later. Set an override value in the Speed out Override and Speed in Override fields in bits per second.
For example, to set an interface to a speed of 100 GB you would enter 100000000000.

https://techdocs.broadcom.com/content/broadcom/techdocs/us/en/ca-enterprise-software/it-operations-management/ca-unified-infrastructure-management-probes/GA/alphabetical-probe-articles/snmpcollector-snmp-data-monitoring/snmpcollector-snmp-data-monitoring-release-notes/snmpcollector-known-issues-and-workarounds.html