It seems that DNS conditional forwarders are being ignored on a Windows 2012R2 server and I can't figure out what is going on exactly.
Situation as is explained: There are two sites A + B with two domains X + Y.
Site A: Domain X / Network: 192.168.1.0/24 Two Windows Domain controllers/DNS Servers/DHCP Servers (W2016 Servers) DNS Conditional forwarders to both DNS servers in Site B Secondary dns prefix by GPO for resolving host names without the need for FQDN.
Site-To-Site VPN IPSEC connection in between. Firewall: Public IP Site A is able to discover whole Site B Firewall: Network Site A is able to discover whole site B Firewall: Public IP Site B is able to discover whole Site A Firewall: Network Site B is able to discover whole site A
Site B: Domain Y / Network: 192.168.10.0/24 Two Windows Domain controllers/DNS Servers/DHCP Servers (1x W2012R2 & 1x W2016 servers) DNS Conditional forwarders to both DNS servers in Site A Secondary dns prefix by GPO for resolving host names without the need for FQDN.
On site A everything is working as expected. I can ping IP's, FQDN, hostnames and access all resources I want. Everything for domain Y is forwarded to the DNS servers in Site B and handeld correctly.
Now the problem is at site B, while all settings are exactly the same (checked this 5 times) only IP is working. So I can access everything on Site A by IP address but nothing else. Whatever I set for conditional forwarder it seems to be totally ignored. By pinging domain X, I get a public IP. When I remove the public dns record it just says that it cant find any host with that name. (Again, I can ping and RDP to the DC's at Site A).
I kinda tried all google search results (also from this forum) without luck. Appreciate the help!