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I need a sensor to monitor QOS through NAT to a server being another NAT



The QOS sensor doesn't seem to work when the server and the destination are behind two different NATs. The ports get all messed up in translation.

delay jitter nat qos

Created on Sep 8, 2016 3:23:44 PM

3 Replies



Could you post a schematic of the network? Did you make sure that the ports are forwarded properly?

Created on Sep 9, 2016 2:12:56 PM by  Stephan Linke [Paessler Support]



The post was actually so I could answer my own question. I created add on sensor and reflector to solve the issue. The problem with both sides being behind that NAT, without static outbound translations being configured the port traffic doesn't get back to where it is supposed to. The code is in c# and can be modified. It is an XML EXE Sensor.

The reflector will need to run on a system with the port forwarded to it. I have it running at my office and multiple clients use it to monitor their internet quality.


Created on Sep 9, 2016 7:09:23 PM



Oh well :D The question is a bit specific and might be hard to find, you may want to generalize it a bit :)

Created on Sep 12, 2016 5:17:01 AM by  Stephan Linke [Paessler Support]

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