Network Management

Troubleshoot interface utilization for NPM

This article provides information and troubleshooting steps for an issue when Network Performance Monitor (NPM) reports 0% interface utilization.

First published date

10/22/2018 3:31 PM

Last published date

2/21/2022 6:09 PM

Overview

This article covers NPM's issue when reporting 0% interface utilization.

Product section

Network Performance Monitor

Resolution

To verify this, you need two SNMP Walks from the device with the issue at least 10 minutes apart. Use the SolarWinds SNMP Walk tool to get the SNMP Walks found in C:\Program Files (x86)\SolarWinds\Orion\SnmpWalk.exe.

 

EXAMPLE:

 

In this instance, the SNMP walks were collected 2hr 22 minutes [8520 seconds] apart, and interface with the issue was GigabitEthernet0/0/0.500

 

Interface Index = 8 (.1.3.6.1.2.1.2.2.1.2.8 = STRING: "GigabitEthernet0/0/0.500")

Interface Speed - 1.3.6.1.2.1.2.2.1.5.8 = GAUGE32: 1000000000 = 1Gbps
 

%RECV Utilization:

  • InOctets Walk2: 1.3.6.1.2.1.2.2.1.10.8 = 5785523
  • InOctets Walk1: 1.3.6.1.2.1.2.2.1.10.8 = 4852921
  • Difference: 932602 octets [7460816 bits]
  • Bits per sec: 7460816 / 8520 = 875 bps
  • Utilization: 875 / 1000000000 * 100 = 0.0000875% = 0%

 

%XMIT Utilization:

  • OutOctets Walk2: 1.3.6.1.2.1.2.2.1.16.8 = 10834

  • OutOctets Walk1: 1.3.6.1.2.1.2.2.1.16.8 = 10322

  • Difference: 512 octets [4096 bits]

  • Bits per sec: 4096/ 8520 = 0.48bps

  • Utilization: 0.48 / 1000000000 * 100 = 0.000000048% = 0%

 

As from the data above, the 0% interface utilization reported by NPM is correct after rounding the calculated value. But to be as close to the "live" utilization you should always collect data in much smaller time intervals (2-5 minutes).