Active Directory Best Practices

1. Domain Controller Configuration

Use at least two domain controllers for redundancy
Place domain controllers in different physical or virtual locations
Configure automatic updates for all domain controllers
Use dedicated servers for domain controllers; avoid installing other roles

Tip: Consider using Read-Only Domain Controllers (RODCs) for branch offices or locations with lower security.

2. Active Directory Structure

Design a logical and scalable OU structure
Use descriptive naming conventions for OUs, users, and groups
Implement the principle of least privilege when delegating administrative access
Regularly review and clean up unused objects

Tip: Use PowerShell scripts for bulk management and reporting of AD objects.

3. Group Policy Management

Use Group Policy Objects (GPOs) to manage user and computer settings
Implement a hierarchical GPO structure
Regularly test and review GPOs
Use GPO modeling and resultant set of policy (RSoP) tools for troubleshooting

Warning: Avoid creating too many GPOs, as it can increase logon times and complicate management.

4. Security Best Practices

Implement strong password policies
Enable and configure auditing for critical events
Regularly monitor and analyze security logs
Use Multi-Factor Authentication (MFA) for administrative accounts
Implement the principle of least privilege for user and service accounts

Tip: Consider using Microsoft's Advanced Threat Analytics (ATA) for enhanced security monitoring.

5. Backup and Disaster Recovery

Perform regular backups of Active Directory
Test restore procedures periodically
Document disaster recovery procedures
Implement a backup retention policy

Warning: Never restore a domain controller from an outdated backup without understanding the potential consequences.

6. Performance Optimization

Monitor and optimize Active Directory database performance
Configure appropriate site links and replication schedules
Use administrative tools like ADSI Edit cautiously
Regularly defragment the Active Directory database

Tip: Use built-in Windows tools like Performance Monitor to track AD performance metrics.

7. Documentation and Change Management

Maintain up-to-date documentation of your AD infrastructure
Implement a change management process for AD modifications
Regularly review and update AD-related policies and procedures
Conduct periodic AD health checks and assessments

Additional Resources