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DNS server does not respond



Our customer has a question would like to ask:

“The below problem happens all the time. To press the button of SCAN NOW, which won’t show Warning messages. Could you help to check this issue? Thank you in advanced.”

The DNS server does not respond. To resolve this issue, check if the DNS service on the remote host may be shut down. Also check if a firewall or IPS between the monitoring server and the remote host is sending a reject for the connection. Or tap the connection with a packet analyzing tool to see if the PRTG probe queries the correct DNS. (code: PE002)

dns notifications prtg

Created on Sep 30, 2021 3:14:57 AM

1 Reply



They'd probably need to instigate a help ticket from

Setup --> Contact Support

on the webconsole.

As for the issue, if you were to get the url/dns/whatever they are trying to do, logon to the PROBE (not the CORE) and run it manually from there.

e.g. if they are trying to scan https://www.google.co.uk with a HTTP Advanced sensor, they'd logon to the PROBE and open a browser and type "https://www.google.co.uk" in, (or try a ping from the PROBE against the DNS etc...)

If DNS fails there when accessed manually from the PROBE server - thats a good starting point.

Created on Dec 10, 2021 2:56:53 PM

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.