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The VMware ESX(i) Disk sensor cannot parse any reply data. What can I do?



I monitor free disk space on my VMware ESX(i) system via SSH. Unfortunately, the SSH VMware ESX(i) Disk sensor returns only the following error message:

Device is not compatible (can not parse reply data). (code PE094)

How can I fix the PE094 error?

disk-free diskspace error error-messages esxi pe094 prtg vmware

Created on Dec 6, 2013 10:48:22 AM by  Gerald Schoch [Paessler Support]

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Accepted Answer



This article applies to PRTG Network Monitor 13 or later

Monitoring Free Disk Space on VMware ESX(i): Unable to Parse Reply Data — Code PE094

If your SSH VMware ESX(i) Disk sensor shows the error code PE094, claiming that the monitored device is not compatible and, thus, parsing the received data is not possible, there might be an issue when executing the df (disk free) command.

Running the df command in a shell, the output probably looks like this: ~ # df Traceback (most recent call last): File "/sbin/df", line 99, in <module> sys.exit(main(sys.argv)) File "/sbin/df", line 53, in main o = eval(output) File "<string>", line 1 Errors: ^ SyntaxError: invalid syntax

This issue often appears when the VMware host is installed on a USB drive. ESX(i) needs a working local USB storage when it boots from USB to be able to make the disk free command work. However, when the USB drive disappears from the system, VMware ESX(i) cannot issue the df command.

Please ensure that you have a local storage for your ESX(i) system to avoid the PE094 error!

Please make also sure that

  • you use the correct credentials for the ESX(i) host,
  • that SSH is enabled on the ESXi host,
  • and also try increasing the Shell Timeout in the sensor settings.

Created on Dec 6, 2013 10:50:31 AM by  Gerald Schoch [Paessler Support]

Last change on Dec 9, 2013 11:04:52 AM by  Gerald Schoch [Paessler Support]

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.