Steps

1. Plan the Active Directory Structure

a. Design the Forest and Domain Structure

• Forest Design: The forest is the top-level container in AD. It should reflect the business structure and organizational requirements. A single forest is recommended for most organizations to reduce complexity.
• Domain Design: A domain represents an administrative boundary in Active Directory. For most organizations, a single domain will suffice, but larger enterprises may require multiple domains.
  • Use a naming convention for domains (e.g., corp.company.com) that is consistent, meaningful, and easy to manage.
• Organizational Units (OUs): Design OUs to reflect your organization’s structure. OUs allow delegation of administrative control and application of Group Policy Objects (GPOs).
  • Structure OUs based on departments, locations, or services for effective management and security policy application.

b. Choose Domain Controllers (DCs) Placement

• Primary Domain Controllers: Choose the first DC for the forest root. This will serve as the primary DC for the domain.
• Additional Domain Controllers: For redundancy and fault tolerance, deploy additional domain controllers across different locations, especially in large enterprises or environments with remote offices.

2. Install and Configure Active Directory Domain Services (AD DS)

a. Install AD DS on the First Domain Controller

• Use the Server Manager to install the Active Directory Domain Services (AD DS) role.
• During the installation, promote the server to a domain controller by selecting the Add a new forest or Add a domain controller to an existing domain option based on your structure.
• Define the Domain Name System (DNS) server, and configure the Global Catalog as necessary.

b. Create and Configure Additional Domain Controllers

• After the first DC is set up, promote additional domain controllers to ensure high availability.
• Use the Active Directory Sites and Services tool to properly configure replication between domain controllers, ensuring they are replicated efficiently and have fault tolerance.

3. Implement Security Best Practices

a. Use Strong Administrative Accounts

• Always use least privilege for administrative accounts to limit access to sensitive areas of the domain.
• Use Dedicated Admin Accounts (DAAs), ensuring that administrative tasks are separated from regular user tasks.
• Avoid using domain administrator accounts for daily tasks like email or web browsing to reduce the attack surface.

b. Implement Multi-Factor Authentication (MFA)

• Configure Multi-Factor Authentication (MFA) for administrative accounts to increase the security of your domain controllers.
• Leverage Azure Active Directory or third-party MFA solutions to enforce this security measure.

c. Secure Domain Controllers

• Place domain controllers in physically secure environments, and use firewalls to restrict access to only trusted systems.
• Disable unnecessary services on domain controllers, such as NetBIOS and SMBv1, which can be exploited by attackers.

d. Audit and Monitor Active Directory

• Configure Audit Policies to track changes to critical AD objects, user logins, and changes to Group Policies.
• Use Advanced Threat Analytics (ATA) or Azure AD Identity Protection to monitor suspicious activities and receive alerts.

4. Configure Group Policy for Management

a. Create and Implement Group Policy Objects (GPOs)

• Group Policy provides centralized management of user and computer configurations. Use Group Policy Management Console (GPMC) to create and apply GPOs to OUs.
• Ensure that critical security settings are enforced through GPOs, such as password policies, lockout policies, and account permissions.
• Use GPO inheritance and filtering to manage which settings apply to different users and computers based on their organizational units or security groups.

b. Use Group Policy Best Practices

• Regularly review GPO settings to ensure they align with current security policies.
• Limit the use of Local Group Policies on workstations, as they can conflict with domain-level policies.
• Implement GPO version control to track changes and prevent accidental misconfigurations.

5. Manage Active Directory Users and Groups

a. Use Naming Conventions for User Accounts

• Use standardized naming conventions for user accounts (e.g., firstinitial.lastname or employee ID) to keep things organized.
• Make use of Active Directory User Attributes to easily categorize users, such as department, title, and manager.

b. Manage User Groups Efficiently

• Use Active Directory Security Groups to manage permissions and access control efficiently.
• Implement the Group Nesting strategy, where groups are nested to create a hierarchy of permissions.
• Avoid placing users directly into groups; instead, assign them based on roles or responsibilities.

c. Regularly Clean Up and Maintain AD Accounts

• Implement automated scripts to periodically check for inactive accounts and delete or disable them as needed.
• Regularly audit user accounts, groups, and permissions to ensure they are in line with the organization’s security and compliance policies.

6. Optimize Active Directory Performance and Scalability

a. Configure Active Directory Sites and Services

• Set up Active Directory Sites and Services to manage replication between DCs in different physical locations.
• Ensure that sites are correctly configured with subnet mappings to optimize network traffic and replication schedules.

b. Use Read-Only Domain Controllers (RODCs)

• In branch offices or remote locations where physical security is a concern, deploy Read-Only Domain Controllers (RODCs) to provide a local DC without the full security risk of writable DCs.

7. Backup and Disaster Recovery

a. Regularly Back Up Active Directory

• Use the Windows Server Backup tool to schedule regular backups of the system state, which includes the Active Directory database.
• Store backups securely and test recovery procedures to ensure that they will work during an actual disaster recovery scenario.

b. Implement Disaster Recovery Plan

• Establish a disaster recovery plan for Active Directory that includes a clear procedure for restoring domain controllers and addressing issues like domain corruption or loss.

8. Monitoring and Troubleshooting

a. Monitor Active Directory Health

• Use Active Directory Administrative Center (ADAC), Performance Monitor, and Event Viewer to keep track of AD health and detect potential issues.
• Monitor DNS and replication health regularly to ensure that DCs are communicating correctly and replication is up-to-date.

b. Use PowerShell for Automation

• Automate routine administrative tasks such as user account creation, group management, and reporting using PowerShell scripts.
• Utilize the Active Directory PowerShell module to automate common AD management tasks.