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Netflow V9 NoData



Hi All,

After upgrading the latest version in PRTG, the data on the Netflow v9 sensor began to fail. The data comes back when I wipe the sensor and add it again, but it stops again after 5 minutes. Version number Do you have any ideas related to this topic?

cisco netflow-v9 prtg

Created on Aug 29, 2018 6:25:31 AM

3 Replies



Hi Melih,

Unfortunately, it's a known issue. The sensors are broken in the latest release. Please roll back to the previously installed version. Sorry for the inconvenience!

Kind regards,
Stephan Linke, Tech Support Team

Created on Aug 29, 2018 7:39:41 AM by  Stephan Linke [Paessler Support]



Are you trying to solve this problem? It is not so simple to rollback.

Created on Aug 29, 2018 12:47:46 PM



Yes we are, but there's currently no ETA. The only option at the moment to get the Netflow sensors running again would be to downgrade PRTG to the previous version. Before doing the downgrade, please help us with the following steps:

  1. Go to "Setup"->"System Administration"->"Administrative Tools" in PRTG and run the function "Write Probe Status Files" (https://www.paessler.com/manuals/prtg/administrative_tools_settings.htm). The file(s) will be written into the "Logs (System)"-folder (https://kb.paessler.com/en/topic/463).
  2. Do this 3 times with 5 minutes between the attempts.
  3. Please send us the content of this folder from the respective (Remote) Probe running this sensor. To upload the Probe State files and the PRTG system logs to our FTP server, use the button "Send Logs to Paessler..." on the Tab "Logs and Infos" in the "PRTG Administration Tool" from the system of the probe on which these Netflow sensors are running on (https://www.paessler.com/manuals/prtg/prtg_probe_administrator#logs). This is important in case you are using Remote Probes.
  4. Is it possible to delete the toplists? This is a long shot, but would be great to test it. If you understandably don't want to do it, on the production sensor, please clone the sensor. And wait until the cloned sensor goes gray, then delete all toplists of the clone, pause and restart the sensor and see if it helps.

Thank you so much!

If you're going to downgrade, make sure to disable to Auto Update before hand. You'll find the settings under "Setup | Auto-Update | Settings". Please choose "Automatically download the latest version and alert the admin".

In order to downgrade manually, please follow the steps below:

  1. Stop all PRTG related services
  2. Stop all Virus scanner / Firewall services
  3. Download the installer here: http://download3.paessler.com/support/rollback/prtg_stable.zip
  4. Run the installer
  5. Start all services again

Please let me know if this helped with your problem.

Created on Aug 29, 2018 1:35:46 PM by  Stephan Linke [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.