I have a Windows Server 2012 domain controller with DNS Server role installed. I configured several DNS servers as forwarders and that's working absolutely fine. All DNS requests are resolved.
Now I noticed in my firewall logs, that my DNS server permanently tries to reach gtld-servers.net on port 53, which is blocked by the firewall. Although there are none of these IP's configured as forwarders! Can you tell me, why it does that? I don't see any reason why.
IP's it tries to reach on port 53, but which are blocked: