Contents
In this article, I will explain how to add a domain controller to an existing domain and manage replication links.
Below, an illustration of the final architecture:

Throughout this tutorial, we will add the controller XXXX-AD1 to the existing domain, which already has two controllers on site A.
Prerequisites for XXXX-AD1:
- A version of Windows compatible with the forest and domain level
- Fixed IP
- DNS: one of the DC servers of site A
When adding the first Windows Server 2016/2019 domain controller to an existing environment, the domain must be at least at the 2008 functionality level and the user account used for promotion must be a member of the Schema Administrators and Administrators groups of enterprise, changes to the Active Directory schema are made.