Domain controller

From Wikipedia, the free encyclopedia

A domain controller (DC) is a server[1][2] that responds to security authentication requests within a computer network domain. It is a network server that is responsible for allowing host access to domain resources. It authenticates users, stores user account information and enforces security policy for a domain.[3] It is most commonly implemented in Microsoft Windows environments (see Domain controller (Windows)), where it is the centerpiece of the Windows Active Directory service. However, non-Windows domain controllers can be established via identity management software such as Samba and Red Hat FreeIPA.


The software and operating system used to run a domain controller usually consists of several key components shared across platforms. This includes the operating system (usually Windows Server or Linux), an LDAP service (Red Hat Directory Server, etc.), a network time service (ntpd, chrony, etc.), and a computer network authentication protocol (usually Kerberos).[4] Other components, such as a public key infrastructure (Active Directory Certificate Services, DogTag, OpenSSL) service and Domain Name System (Windows DNS or BIND) may also be included on the same server or on another domain-joined server.[5]


Domain controllers are typically deployed as a cluster to ensure high-availability and maximize reliability. In a Windows environment, one domain controller serves as the Primary Domain Controller (PDC) and all other servers promoted to domain controller status in the domain server as a Backup Domain Controller (BDC).[6] In Unix-based environments, one machine serves as the master domain controller and others serve as replica domain controllers, periodically replicating database information from the main domain controller and storing it in a read-only format.[7]

See also[edit]


  1. ^ "Domain Controller Roles". Microsoft TechNet. Retrieved Dec 4, 2009.
  2. ^ "Domain Controller Roles". Windows Server 2003 Technical Reference. Microsoft TechNet. 2010-06-03. Retrieved 2012-11-21.
  3. ^ "14.3.3. Domain Controller".
  4. ^ "Chapter 1. Introduction to FreeIPA". Archived from the original on 2022-04-07. Retrieved 2020-01-02.
  5. ^ "How to Find Expired Domains". Domain Hunting Guides. 2023-02-06. Retrieved 2023-04-15.
  6. ^ "Domain Controller Roles". Microsoft Tech net 3 June 2010. Retrieved 13 February 2011.
  7. ^ "V4/Replica Setup - FreeIPA".