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HTTP/1.1 500 Internal Server Error on VMware ESX Server



Dear Support,

Currently we have a strange issue with our software. I monitor an ESX server via the vSphere Web Access (VMware ESX Server sensor)

It has 24h autodiscovery enabled to detect and monitor new created servers. From time to time it shows servers UP which are 100% down , and visa versa.

This is a very odd behaviour.

For servers that are 100% UP the sensor says :

Status down : HTTP/1.1 500 Internal Server Error

All servers are monitored from 1 monitor server. I cannot find any difference in the servers. I already re-run the auto configuration after deleting some servers that were down however the result is the same.

Is there any explanation to this behavior?

  • PRTG Network Monitor
  • Operating System: Windows 7/2008 R2 (6.1.1 Build 7600 ), 2 CPUs, , on VMware

500 esx http-1-1 internal vmware

Created on Nov 30, 2010 12:46:36 PM

3 Replies



problem description is not clear to us.

what is the server and what are the VMs?

use the terms VM ware host server sensor and VM ware virtual machine sensors

Created on Dec 5, 2010 8:01:21 AM by  Aurelio Lombardi [Paessler Support]



The server is the VMware ESX server as described in the manual of PRTG.

A username and password is needed to read the status of the virtual machines running on the ESX host Server.

I use the HTTPS VMware Protocol to read the status of the VM ware machines via the server sensor.

I run an autodiscovery every 24h. This way I can automatically see new VM's that are created on the ESX server.

The VM ware machine sensors (esxvmsensor) however, show machines that are down (turned of virtually) as UP and visa versa.

This happens in ca. 10% of the cases.

When I log in on the VM ware host server manually and check via the webinterface of the ESX host server it shows the state correctly.

Created on Dec 7, 2010 9:36:50 AM



when adding VM sensors the default setting for powered of machines is to ignore the powered off state.

go to the settings of the sensor and select "Alarm when VM is powered off"

Created on Dec 8, 2010 9:56:53 AM by  Aurelio Lombardi [Paessler Support]

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