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NetFlow V5 / V9 on Sonicwall NSA2400



I am trying to use NetFlow monitor for a Sonicwall NSA 2400.

Both NetFlow V5 and NetFlow V9 seem to bring in a small amount of data but it isn't what is truly going through the link.

I'm seeing it show something like 265kbit/s but I know for certain (because I can check using the Sonicwall Realtime monitor and MRTG, as well as SNMP sensors in PRTG) that it is using at least 6mbps...

I've tried a wide range of timeout settings and the like but no combination appears to yield correct results.

Could anybody assist me in getting this set up? Perhaps PRTG doesn't support Sonicwall's implementation of NetFlow?

bandwidth netflow sonicwall

Created on Mar 23, 2013 2:10:05 PM

1 Reply




seeing as this seems to be a Sonicwall device, there might be an explanation, that Sonicwall does send slightly different Netflow9-packets which do not fully comply with the standard of Cisco Netflow 9 packets (for which the sensors are developed for). The Toplists "ignore" the Active Flow Timeout, but the normal sensor results do not, so it's very likely that this is an issue with the Sonicwall sending packets with a "wrong" active flow timeout (compared to the setting in the Sensor). Unfortunately, as we do not have Sonicwall devices in our lab, we can't test this, but we've seen some cases where the Sonicwalls were not properly working with Netflow 5 or 9 sensors.

best regards.

Created on Mar 25, 2013 3:35:33 PM by  Torsten Lindner [Paessler Support]

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