I currently run a RRAS server with VPN / NAT enabled which also has its own DNS and DHCP role.
I am trying to promote this server to a domain controller (first DC, new Forrest) but I get an error which drives me mental.
Here you can see it can find the working DNS server (which is itself)


But then

Anyone seen this before ? I really don't want to remove the DNS role and let it reinstall it ...