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DNS sensor showing RED on several devices.



Hi, please help.

My prtg is installed on a windows10 VM. The Vm is installed on Parallels Destop on my imac.

I use prtg to monitor various devices on my home network only. Everything works very well except the DNS sensors which remain in the RED state.

I do have one DNS sensor that works ok and that is on my sky hub/router.

Are there any settings in prtg that i need to adjust to mahe the DNS of the the other devices to work?

Thank you


dns prtg sensor

Created on Dec 17, 2019 2:08:01 PM

3 Replies



The DNS sensor only works on devices that are actually responding to DNS queries. Other devices [that don't have a DNS server running] won't work.

Created on Dec 17, 2019 3:12:40 PM by  Stephan Linke [Paessler Support]



Thank you, I have another question please.

When I first installed prtg, the auto discovery found all the devices on my network and it named some by their name, some by their ip address and the remainder were listed as unknown.

How can discover all devices by their name?

Thank you.

Created on Dec 17, 2019 3:33:10 PM



That's a DNS problem hehe. If PRTG cannot resolve the IP to the corresponding DNS name, it will use the IP address instead. Naming them manually is probably easier and quicker.

Created on Dec 18, 2019 12:45:05 PM by  Stephan Linke [Paessler Support]

Disclaimer: The information in the Paessler Knowledge Base comes without warranty of any kind. Use at your own risk. Before applying any instructions please exercise proper system administrator housekeeping. You must make sure that a proper backup of all your data is available.