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Verification on QoS Round trip sensor



I'm trying to get a QoS Round trip sensor working with a remote probe or a QoS reflector. I'd like to get figured out so I can use either a windows box at another site or config and ship a pi.

First: I'm a little confused on ports to open on my Cisco FireWall. I'm trying to connect my PRTG Server ( inside network ) and a Remote Probe on the outside of my FW.

I see references to both TCP 23560 and UDP 50000. But only see UDP 50000 in the Wireshark logs on the remote Probe. Do I need both those ports, opened on my end devices ( windows at this point in time ) forwarded to my PRTG Server as destination ports from the outside -> in?

Second question: I tried to do a PRTG Probe in QoS round trip Sensor settings, but I tested internal -> moved my windows box to another subnet and couldn't find where to update the Target Probe Dropdown menu.

Thank you

firewall-ports qos-reflector qos-remote-probe remote-probe

Created on Mar 13, 2020 4:30:09 PM

1 Reply



Hello Aaron,

Thank you for your post.

1) You must ensure that firewalls or network address translation (NAT) rules allow the UDP packets to reach the target probe. The Windows firewall on the target system is automatically opened by the probe.

2) Did you add the sensor to the Local Probe? If that is the case, then you should be able to select any existing Remote Probe as the target from the drop down menu in the "Settings" of the sensor. Please note that you have to add the Remote Probe, before you add the QoS sensor in order for the Remote Probe to appear in the drop down list.

For more information about this, please see the sensor manual.

Kind regards,
Sasa Ignjatovic, Tech Support Team

Created on Mar 16, 2020 11:26:09 AM by  Sasa Ignjatovic [Paessler Support]

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