I couldn’t reproduce it for now (/cc @m.traeumner)
Tried using following machines as remote DC:
- Windows 2012r2
- NethServer 7.4
Since the error is “Server not found in Kerberos database.”, you probably have some network troubles, maybe only on DNS resolution. Are you sure you don’t have multiple DC on the same forest?
When the messages are showing? During access to the Server Manager?
EDIT: also tested using NS 7.5 as remote DC.