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Reverse Lookup Problem



I have created a reverse lookup zone in my DNS server and fill the zone file manually in order to make my PRTG resolve IP addresses to host names. The prtg server is able to make reverse lookup successfully.(ping and nslookup can resolve IP addresses to host names) When netflow sensor starts receiving data, I can see successful lookups on the web page of the toplists. But after a few days the ip addresses have been failed to be resolved even the operating system (ping, nslookup) of the server is still able to resolve. I reset the DNS server but no success.

dns prtg reverse-lookup

Created on Aug 21, 2018 11:29:01 AM

1 Reply



You could try to run a daily task

ipconfig /flushdns

To make sure it is not your local system DNS cache - this would need to be executed on the probing device.

Other then that - it sounds a bit odd ...

NSLOOKUP is not a sufficient test - while you see that the DNS would respond, you still bypass any local cache on the local device.


Florian Rossmark


Created on Aug 22, 2018 2:41:26 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.