This video is part of a series on installing and configuring Microsoft Active Directory. We’ll add a second domain controller to an existing Active Directory forest and domain using Windows Server 2025. However, the procedures detailed here are the same for Windows Server 2022 and previous versions. We’ll cover the following topics. △ Operating System Preparation △ Promotion to a Domain Controller △ Alternative Promotion Method △ Post Domain Promotion Checks △ A Common Error When Attempting to Join a Domain △ Next Domain Steps Other actions and tasks we’ll cover in this Active Directory series are: 🪟 Standup a new forest and domain using Windows Server Core (no GUI). 🪟 Adding member servers (SQL, DHCP, SCCM, etc.) 🐧 Adding Linux clients as domain members 🪟 Failover clustering. . . . and more. Applies to: Windows Server 2025, Windows Server 2022, Windows Server 2019, Windows Server 2016, Windows Server 2012 R2, Windows Server 2012, Windows Server 2008 R2, Windows Server 2008. Glossary: AD = Active Directory ADDS = Active Directory Domain Services CIDR = Classless Inter-Domain Routing DC = Domain Controller DNS = Domain Name Server DSRM = Directory Services Restore Mode FSMO = Flexible Single Master Operation (pronounced "fizmo") GPO = Group Policy Object GUI = Graphical User Interface IPv4 = Internet Protocol version 4 IPv6 = Internet Protocol version 6 KCC = Knowledge Consistency Checker NetBIOS = Network Basic Input/Output System = New Technology Directory Services Directory Information Tree OU = Organizational Unit SSH = Secure Shell SYSVOL = System Volume Chapters 0:00 Introduction 0:42 Operating System Preparation 3:03 Promote the Computer to a Domain Controller 5:10 Alternative Promotion Method 7:07 Post Domain Promotion Checks 10:24 Common Error When Attempting to Join a Domain 11:13 Next Domain Steps 12:00 Thank you for watching Links: 🌐