Não. Os Serviços de Domínio do Active Directory e o DNS são duas funções de servidor diferentes. Eles trabalham juntos, mas não significa que estejam na mesma máquina. Eu tinha um controlador de domínio que não era um servidor DNS em um site, bem como o contrário, um servidor tinha DNS, mas não AD.
Microsoft Active Directory Domain Services are the foundation for distributed networks built on Windows 2000 Server, Windows Server 2003 and Microsoft Windows Server 2008 operating systems that use domain controllers. Active Directory Domain Services provide secure, structured, hierarchical data storage for objects in a network such as users, computers, printers, and services. Active Directory Domain Services provide support for locating and working with these objects.
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What is the AD DS server role?
AD DS provides a distributed database that stores and manages information about network resources and application-specific data from directory-enabled applications. Administrators can use AD DS to organize elements of a network, such as users, computers, and other devices, into a hierarchical containment structure. The hierarchical containment structure includes the Active Directory forest, domains in the forest, and organizational units (OUs) in each domain. A server that is running AD DS is called a domain controller.