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PRTG DNS resolver



How does PRTG perform DNS resolving? Does it use its own DNS resolver or does it rely on the host OS resolver?

I'm handling a network where monitoring of all firewalls and NW equipment is done on a separate outband subnet. The PRTG probe is located in the same subnet so in case of outage outband management interfaces of all equipment is available for monitoring and troubleshooting. The only problem is that I'm relying on DNS server which isn't in the same subnet and in case of outage, PRTG stops resolving and it's impossible to monitor and troubleshoot the network. One solution would be to setup a slave DNS in the same subnet (perhaps even on the same host) for PRTG to use. But is there a way to force PRTG to use the local resolver cache? Last time I had an outage, PRTG couldn't access the DNS server and stopped polling completely so I was blind to what was happening. Any recommendation is welcome.

cache dns outage resolver

Created on Nov 11, 2015 4:32:36 PM

1 Reply



PRTG uses Windows API calls to resolve DNS. So it's always used directly from the hosts file or the DNS. The cache is never used, if I'm recalling correctly. So slave DNS would be the best way to provide monitoring in case of an outage :)

Created on Nov 12, 2015 9:39:12 AM 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.