AZ-802 Study Guide: Building a Multi-DC Active Directory Forest (Part 1): Subnets, Replication, and Group Policy

How I built a multi-domain controller Active Directory forest using Hyper-V, configured custom sites and subnets, resolved DNS traps, and established Group Policies and gMSAs for a production-grade hybrid lab.

📖 AZ-802 Study Series: This is Part 1 of my hands-on lab series leading up to the Microsoft AZ-802 exam. If you are just starting out, check out The Ultimate Guide to Windows Server Hybrid Administrator Associate (AZ-802) Study Guide for the complete roadmap, study resources, and lab prerequisites.

Note: The Microsoft AZ-802 (Configuring Windows Server Hybrid Advanced Services) exam is currently in beta, with General Availability (GA) expected soon. Getting certified early is a strategic opportunity to get ahead and validate hybrid identity and infrastructure capabilities before the certification goes mainstream.

Why Build a Local AD Forest?

If you are studying for the Microsoft AZ-802 (Configuring Windows Server Hybrid Advanced Services) exam, or targeting corporate systems engineer roles, you quickly realize that cloud-only identity isn't the whole story. Most enterprises run a hybrid model: local Active Directory Domain Services (AD DS) synced to Microsoft Entra ID in the cloud.

To test hybrid synchronization, Azure Arc onboarding, and Failover Clustering, you need a local Active Directory forest. Without it, you have no local domain join targets, no Group Policies (GPOs), and no Kerberos authentication.

This is Part 1 of my multi-part Windows Server Hybrid Administrator series. In this post, I lay down the directory foundation manually. While setting up a domain and replication manually takes a bit of time, doing it by hand is the best way to embed the underlying knowledge, as these configuration steps and options are heavily tested in the AZ-802 exam.

In Part 2: Automating Windows Server Lab Setup, I automate this entire VM provisioning process to make future lab teardowns and redeployments instantaneous. If you prefer to deploy everything automag…