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Question on Sensors and License Numbers




I am trying to wrap my head around the sensor and license relationship.

For simplicity say for example i want to monitor 500 devices with just the Ping Sensor. What license would I need? Apologies for the noob question. I just want to make sure I understand the licensing and sensor relationship in order to assess if PRTG will best suit our needs.

capacity licensing sensor

Created on Aug 27, 2019 9:52:56 AM

4 Replies



Hi there,

The answer would be "500" then, though to be precise, when you install PRTG, by default there will be a "Probe Device" which represents the machine where PRTG is installed and it has three standard sensors that cannot be deleted (Core Health, Probe Health, System Health), so you have effectively 497 sensors left to use unless you pause those sensors, because manually paused sensors do not count against your license.

See also this video for more details.

Kind regards,


Created on Aug 27, 2019 10:04:22 AM by  Erhard Mikulik [Paessler Support]



oh ok..so basically sensor count is directly proportional to the the number of devices I want to monitor? The way I understood it was i could re-use the Ping sensor for a pool of devices. I guess that is wrong.

Created on Aug 28, 2019 12:11:32 AM



ok..seems i mis understood the concept of licensing around the sensors. From what you described it seems that license count will still be dependent on device count in my scenario. So each device will eat up once license space. the way I previously understood licensing was that the ping sensor would just cost as 1 license and you could apply it to a pool of devices.

Created on Aug 28, 2019 3:20:28 AM



Correct, it's not like "Add a ping sensor floating somewhere in the tree and then define there a range of targets to ping".

There is sort of an object hierarchy. You need a device to put sensors on. Most sensors will direct their query then to the device they were added to.

Device count as such is not really a deciding factor, what I mean is, in the end it doesn't matter whether you have 500 ping sensors spread over 500 devices or you monitor 100 devices and each with 5 different sensors on them. So the 500 sensors license is a good fit for small networks or when only aiming at monitoring certain devices in your network where 500 sensors could suffice. For everything else then there are those larger licenses.

Created on Aug 28, 2019 7:30:36 AM by  Erhard Mikulik [Paessler Support]

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