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prtg not listening netflow UDP Port

Votes:

0

Hello,

I am exploring PRTG free version & trying to check application/port level network BW visibility from CISCO Router. i have configured flow export on CISCO router & able to get netflow on netflow tester but not in prtg.

while trying to add sensor under probe device, unable to see prtg server IP under "Receive netflow packets on IP" & getting message as "No Receive NetFlow Packets on IP available" which seems prtg is not listening for netflow.

Kindly suggest where to enable it.

Dhiraj

bandwidth-monitor netflow prtg

Created on May 14, 2018 2:31:48 PM



5 Replies

Votes:

0

Hello Dhiraj,

Please try restarting the PRTG host and add a new NetFlow sensor then to see if it makes a difference. If you still experience the issue, please send us a support bundle ("Setup | Contact Support") for further investigation.

Kind regards,

Erhard

Created on May 15, 2018 11:51:48 AM by  Erhard Mikulik [Paessler Support]



Votes:

0

Hello Erhard,

Strange, after system restart able to see local IP under Receive NetFlow Packets on IP & able add netflow v9 sensor.

But now not getting netflow data on this sensor. CISCO Router shows correct flow export but not able to see under sensor.

i have below config on CISCO Router & prtg netflow v9 sensor end.

CISCO Router Configuration

ip flow-export source GigabitEthernet0/1 (WAN Port) ip flow-export version 9 ip flow-export destination 10.0.0.200 2055 ip flow-cache timeout active 1 ip flow-cache timeout inactive 15

Probe Netflow v9 1 Sensor Configuration

Receive NetFlow Packets on UDP Port : 2055 Sender IP : 43.88.82.254 Active Flow Timeout (Minutes) : 3 Receive NetFlow Packets on IP : 10.0.0.200

Kindly suggest what else need to be check to get netflow on prtg sensor.

Dhiraj

Created on May 16, 2018 7:48:36 AM



Votes:

0

Hello Dhiraj,

Flow Timeout in the sensor should be ideally one minute higher than what'S configured in the sending device. Also check with NetFlow Tester if you indeed see flows coming from ip 43.88.82.254, if not, the sensor won't process the data unless the ip matches or you can also leave "Sender IP" empty, then it will process all flows coming in on port 2055, regardless of which sender.

Kind regards,

Erhard

Created on May 16, 2018 9:55:12 AM by  Erhard Mikulik [Paessler Support]



Votes:

0

Hello Erhard,

Thanks for the response. i have removed Sender IP & started getting netflow data. My requirement is to get netflow data from multiple CISCO Routers under separate sensors. if will use netflow without sender IP, all data will get aggregate on single sensor & will not be able to see exact data from each sender.

It's strange if i remove sender IP, m getting netflow data but if i specify actual source, stopped getting. same source data i can see through netflow tool.

Regards, Dhiraj

Created on May 23, 2018 3:11:53 PM



Votes:

0

Hello Dhiraj,

Please send me an email ([email protected]) with the following details for further analysis:

  • Screenshots NetFlow sensor's "Overview" and "Settings" tab
  • Screenshots of NetFlow Tester after it was running for a few minutes and receiving flows (you need to pause the NetFlow sensor, otherwise NetFlow Tester cannot listen on the port)
  • Save decoded flows and templates in NetFlow Tester and attach them as well to the email.

Thank you in advance.

Kind regards,

Erhard

Created on May 24, 2018 9:22:04 AM by  Erhard Mikulik [Paessler Support]




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