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How to solve a 'not found' error when monitoring VMware ESX(i) servers?



  • I am monitoring ESX / ESXi 4.x systems using sensors I created in PRTG 9.1 or earlier. On high load (CPU above 80 - 85%) PRTG reports a 'not found' error for those sensors.
  • I am monitoring ESX / ESXi 4.x or 5.x systems using sensors I created in PRTG 9.2 or higher. PRTG reports a CPU-load of 100% and higher for this server and I am not aware that any of my virtual machines is creating this load.

What can I do about this?

error esx esxi not-found vmware vsphere

Created on Feb 27, 2012 1:55:13 PM by  Daniel Zobel [Product Manager]

Last change on Feb 27, 2012 2:51:09 PM by  Daniel Zobel [Product Manager]

1 Reply

Accepted Answer



This article applies to PRTG Network Monitor 9 or later

Processes 'Hanging' on ESX Server

If your VMware CPU sensors report unusually high CPU load and you're pretty sure that those systems do not actually consume as much CPU performance, there might be processes 'hanging' on your VMware system. Usually, this is resolved by a reboot of your VMware hosts.

However, sometimes a reboot is not an option.

Forced Close of 'Hanging' Processes

WARNING: The procedures described in this article are intended for experienced users only! The suggested commands can lead to system crashes and might also cause data loss on your target systems. We recommend you always keep a proper backup at all times.

Connect via SSH, View Processes

In this case, enable SSH on your host(s) and connect using an SSH command line client.

Using the command esxtop or top you can view the top list of running processes (type q to quit).

In the %SYS column (esxtop)—respectively the %CPU column (top)—you see the current load of the single processes.

Determine Critical Processes

Check if you see one or more of the following processes with high resource consumption. If they exist there are 'hanging' SSH sessions in the background and you should close them:

  • ESXi 4.x: Process named Dropbear (i.e. the busybox implementation of SSH)
  • ESX 4.x or ESXi 5.x: Process named sshd

Determine IDs of Processes

Commands vary depending on the version of the ESX(i) host. Please see table below.

SystemExecute CommandWhere to find Process ID
ESX 4.xps -ef | grep sshd:First number after the user name
ESXi 4.xps | grep dropbearFirst number in the line
ESXi 5.xps | grep sshdFirst number in the line

Kill Processes

Warning: Follow these instructions only if you know what you're doing! The following commands will also end your own remote SSH connection (and you'll have to reconnect).

For each process, execute the command kill -9 <processID> (replace <processID> by the ID you determined before).


This should solve the issue without rebooting your ESX(i) hosts.

Created on Feb 27, 2012 2:18:50 PM by  Daniel Zobel [Product Manager]

Last change on Feb 27, 2012 4:36:25 PM by  Daniel Zobel [Product Manager]

Disclaimer: The information in the Paessler Knowledge Base comes without warranty of any kind. Use at your own risk. Before applying any instructions please exercise proper system administrator housekeeping. You must make sure that a proper backup of all your data is available.