It is very odd when I used my DC01 > Tools > Active Directory Sites and Services. I get “…Domain does not exite or cannot be contacted”. But if I use DC02 it was fine, same subnet and has been linked between DC01 and DC02 successfully. I attempted to Add Roles and Feature, DC01 already has it installed. What exactly DC01 asking for? Please see image, thanks a bunch!
Your Ethernet, has an exclamation mark, can you point at it and see what error it give?
@alexander.kok also send a screenshot or the output of your ipconfig /all results.
DC01 pinging DC02 and ITFROUTE01. All ping successfully. After I used DC02 to add Sites and Services, I can now see Sites and Services on DC01. When I rolled mouse over the Ethernet Exclamation mark, it says Unidentified Network, No internet access. But I can ping 126.96.36.199 and browse internet just fine.
Nice! Looks like you got it all sorted out then. Good job!