Active Directory sites, topology, and replication

Advanced
Administrator
Windows Server

Build and validate Active Directory site topology and troubleshoot the replication that flows over it, including Windows Server 2025 priority boost.

Learning objectives

In this module, you'll:

  • Design Active Directory sites, subnets, site links, and costs.
  • Explain Knowledge Consistency Checker (KCC), Inter-Site Topology Generator (ISTG), bridgeheads, and connection objects.
  • Identify topology anti-patterns and validate Domain Controller (DC) Locator and replication behavior for Windows Server 2025 readiness.
  • Explain Update Sequence Numbers (USNs), high-watermarks, and up-to-dateness vectors and inspect linked-value and deleted-object metadata.
  • Diagnose replication failures and apply replication priority boost in controlled scenarios.

Prerequisites

  • Experience with Active Directory Sites and Services and Active Directory Domain Services (AD DS) replication concepts.
  • Experience with Repadmin, AD DS replication, and domain controller operations.