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What to do when NetFlow data drops?



Every now and then , I am getting this error. How to fix it.

ToDo: Info Subject: Netflow data dropped (code: PE082) Message: The netflow sensor has received and dropped flows with a timestamp older than the timespan defined by the active flow timeout. Please ensure that the active flow timeout from the sensor setting matches the flow timeout set in the flow exporter device (code: PE083)

The active timeout is fixed @ default 30mins..

flow-timeout netflow-v5 prtg

Created on Aug 4, 2010 3:02:26 AM

Last change on Aug 12, 2010 9:25:09 AM by  Daniel Zobel [Product Manager]

3 Replies

Accepted Answer



The active flow timeout in PRTG should be set one minute larger than the timeout on the device.

We recommend to set the active flow timeout on the device to 5 minutes and in PRTG to 6 minutes.

Please also check if you have a Long Aging Timer entry for the device when getting the error PE083. The command in case would be mls aging long

By default this value would be set to 1920 seconds. If you do have this value entry, please reduce the same and try again.

Created on Aug 4, 2010 8:19:10 AM by  Aurelio Lombardi [Paessler Support]

Last change on Feb 24, 2014 4:45:20 PM by  Gerald Schoch [Paessler Support]



Hi team,

I use netflow on a Cisco 6509 with the active flow timeout set to 5 minutes. In the PRTG flowsensor settings I have set the timeout to 6 minutes, however I still get regular PE082 dropped flow errors. Is there anything else that can be done?

Thanks in advance,

Regards, Anne

Created on Oct 17, 2012 3:03:09 PM




how many flows do you get?

what filter rules are you using?

please take a look at


Created on Oct 18, 2012 4:27:22 AM by  Aurelio Lombardi [Paessler Support]

Last change on Dec 2, 2021 10:23:58 AM by  Maike Guba [Paessler Support]

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