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No Netflow Data in PRTG



I have a Fortigate 100D firewall and I am trying to monitor Bandwidth through PRTG. I am trying to use NetFlow V5 sensor but it is not populating any data. If I turn off PRTG services and use NetFlow tester it sees packets reaching my PRTG server on the ports I have configured. As soon as I start up PRTG the NetFlow tester no longer receives any packets.

Fortigate config:

config system netflow
    set collector-ip
    set collector-port 9997
    set source-ip
    set active-flow-timeout 1
    set inactive-flow-timeout 15
    set template-tx-timeout 30
    set template-tx-counter 20

fortigate netflow prtg

Created on Feb 19, 2018 4:34:44 PM

Last change on Feb 20, 2018 11:58:06 AM by  Stephan Linke [Paessler Support]

1 Reply



That's normal and expected behaviour, since one of the two needs to bind the port in order to receive flow packets. Could you provide a screenshot of the flow tester? I won't publish it, if you're worried about disclosing confident data. Please also provide screens of the sensor configuration.

Kind regards,
Stephan Linke, Tech Support Team

Created on Feb 20, 2018 11:55:31 AM by  Stephan Linke [Paessler Support]

Last change on Feb 20, 2018 11:58:20 AM 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.