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Loss of data



Hi Team,

Earlier this morning our PRTG server suddenly reported a grey status on around 99% of the sensors on our install. This state persisted for around 11 minutes until they all came back up without outside intervention. Could you please give us some assistance in getting to the bottom of this? What details would you need to aid the investigation? Many thanks in advance.


Rob Hamilton

grey-sensors no-data prtg13

Created on May 11, 2014 8:26:58 AM

3 Replies




thank you very much for your KB-Post. The next time there are grey sensors, or if there are still grey sensors, please go to the "Setup"->"System Administration"->"Administrative Tools"-Page in PRTG and click the button "Write Probe state file". The state file(s) should be written into the "Logs (System)"-folder, please send us the content of this folder. Please also forward us a screenshot of the overview page of one grey sensor, a screenshot of the Live graph and live data table of this sensor and a screenshot of the "Setup"->"System Status"-Page in PRTG. Then use the option to upload the state files and the PRTG System logs to our FTP-Server, using the button "Send Logs to Paessler..." on the tab "Logs" in the "PRTG Probe Admin Tool". You can do this from the Probe that runs these sensors (Important if you are using Remote Probes!)

In case it is necessary to send the files by mail, you will find the state and log files within the data directory as defined under the "Core Server" tab of the "PRTG Server Administrator" tool, or in the following default paths:

XP/2003: C:\Documents and Settings\All Users\Application Data\Paessler\PRTG Network Monitor\Logs (System)
Vista/2008/Windows 7: C:\ProgramData\Paessler\PRTG Network Monitor\Logs (System)

Please be aware that it might also be a 'V7' or a 'V8'-folder in which then the "Logs (System)"-folder resides. Please send the entire "Logs (System)"-Folder as a zip file then.

Please then contact us via email to [email protected] with these screenshots & logs.

best regards.

Created on May 12, 2014 11:40:04 AM by  Torsten Lindner [Paessler Support]



Many thanks for your update. We will try and capture the data when the outages occur and send it on to you. Unfortunately they can be very short and we can't always get there in time to capture it.

We are currently running PRTG Network Monitor x64 on a Windows 2008 R2 box (virtualised instance).

Is there anything else we can check in the meantime to rule out as a root cause etc?

Many thanks,


Created on May 27, 2014 2:16:26 PM



Please follow the tips outlined in I run PRTG on VMware. How can I obtain best performance?, even if you are using a different virtualising system, and also, it won't hurt to update to the latest PRTG version 14.2.10.

Created on May 27, 2014 2:22:26 PM by  Torsten Lindner [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.