Learn More About Windows Update Server 2012 R2
You can install Essentials as a member server in a domain of any size. Previously, Windows Server 2012 Essentials can be used as the only domain controller of a small office network. Now Windows Server 2012 R2 Essentials can be installed on a virtual server and a member server in an existing domain of any size. When installing as a member server, you can have more than one server running Essentials.