Implement Microsoft Entra Private Access for Active Directory domain controllers
Implementation Effort: Medium
User Impact: High
Overview
Microsoft Entra Private Access enables secure, policy-driven access to on-premises Active Directory domain controllers by removing broad network trust and enforcing Zero Trust principles. Instead of exposing domain controllers over flat networks or VPNs, access is brokered per-resource using identity, device health, and Conditional Access policies.
Implementation steps:
- Install Components: Deploy Private Network Connector, Private Access Sensors on domain controllers, and Global Secure Access Client on endpoints
- Configure Applications: Publish domain controllers and define Service Principal Names (SPNs) for protected resources
- Apply Security Policies: Create Conditional Access policies with MFA requirements and assign to synchronized AD users
- Test and Enforce: Validate functionality in audit mode, then switch to enforcement
This approach eliminates implicit network trust, minimizes attack surface, and ensures that only authorized and healthy users/devices can access domain controllers, aligning legacy authentication with modern Zero Trust security. Specifically:
- Zero Trust Network Access (ZTNA): Replaces traditional VPN broad network access with granular, application-specific access
- Enhanced MFA Coverage: Extends multifactor authentication to legacy on-premises applications that don't natively support modern authentication
- Privileged Access Protection: Secures domain controllers with enforced MFA and Privileged Identity Management (PIM)
- Lateral Movement Prevention: Eliminates excessive network access and prevents unauthorized lateral movement within the network