Azure Private Link is a crucial networking security feature that enables you to access Azure PaaS services (such as Azure Storage, Azure SQL Database, and Azure Cosmos DB) and Azure-hosted customer-owned services over a private endpoint within your virtual network. This technology ensures that traf…Azure Private Link is a crucial networking security feature that enables you to access Azure PaaS services (such as Azure Storage, Azure SQL Database, and Azure Cosmos DB) and Azure-hosted customer-owned services over a private endpoint within your virtual network. This technology ensures that traffic between your virtual network and the service travels entirely over the Microsoft backbone network, eliminating exposure to the public internet.
Key components of Private Link include:
**Private Endpoints**: These are network interfaces that use private IP addresses from your virtual network. When you create a private endpoint, it establishes a secure connection between your VNet and the Azure service. The private endpoint receives an IP address from your subnet's address range.
**Private Link Service**: This allows you to create your own Private Link-enabled service behind an Azure Standard Load Balancer. Service providers can offer their services to consumers who connect via private endpoints in their own virtual networks.
**Benefits for Security**:
- Data exfiltration protection: Traffic remains on the Microsoft network
- Granular access control through Network Security Groups (NSGs)
- No public IP addresses required for accessing services
- Services appear as local resources within your virtual network
- Cross-region and cross-tenant connectivity support
**DNS Configuration**: Proper DNS setup is essential for Private Link. You typically integrate with Azure Private DNS zones to resolve the service's FQDN to the private endpoint IP address. This ensures applications connect through the private path rather than public endpoints.
**Use Cases**:
- Securing access to Azure PaaS services from on-premises networks via VPN or ExpressRoute
- Multi-tenant SaaS scenarios requiring isolation
- Compliance requirements mandating private connectivity
- Hybrid cloud architectures requiring secure service consumption
Private Link supports both regional and global deployments, making it versatile for enterprise architectures requiring stringent network security controls.
Private Link Services - AZ-500 Exam Guide
Why Private Link Services are Important
Private Link Services are crucial for Azure security because they enable you to expose your services privately to consumers while keeping all traffic on the Microsoft backbone network. This eliminates exposure to the public internet, significantly reducing the attack surface and protecting against data exfiltration threats. For organizations handling sensitive data, Private Link ensures compliance with regulatory requirements by maintaining traffic within a private network boundary.
What are Private Link Services?
Azure Private Link Service is a feature that allows you to create your own private link service powered by Azure Standard Load Balancer. This enables consumers in other virtual networks (even in different Azure AD tenants or subscriptions) to access your service privately through a Private Endpoint.
Key components include: • Private Link Service - Your service behind a Standard Load Balancer that you want to share privately • Private Endpoint - A network interface that connects consumers privately to your service • NAT IP Configuration - Source NAT addresses used to translate consumer private IP to your service's VNet IP
How Private Link Services Work
1. Service Provider Setup: Create a Standard Load Balancer with your application VMs in the backend pool 2. Create Private Link Service: Associate the Private Link Service with the Load Balancer's frontend IP configuration 3. Configure NAT IPs: Specify a subnet for NAT IP addresses that will be used for source address translation 4. Share the Alias: Provide the service alias or resource ID to consumers 5. Consumer Connection: Consumers create a Private Endpoint in their VNet using the alias 6. Approval: Service provider approves or auto-approves the connection request 7. Private Connectivity: Traffic flows privately through the Microsoft backbone
Key Features to Remember
• Visibility Control: Control who can discover and connect to your service using visibility settings • Auto-Approval: Configure subscriptions that can automatically connect • TCP Proxy V2: Retrieve consumer's source IP address using proxy protocol • Global Reach: Services can be accessed from any Azure region • Cross-tenant Support: Works across different Azure AD tenants
Exam Tips: Answering Questions on Private Link Services
Scenario Recognition: • When a question mentions exposing services privately to external consumers or partners, think Private Link Service • Questions about hiding your service from the public internet while allowing specific access point to Private Link • Multi-tenant scenarios requiring private connectivity indicate Private Link Service
Key Differentiators to Remember: • Private Endpoint vs Private Link Service: Private Endpoint is the consumer side; Private Link Service is the provider side • Standard Load Balancer Requirement: Basic Load Balancer does NOT support Private Link Service • NAT Subnet: Must be configured and cannot overlap with backend pool subnet
Common Exam Scenarios: • Configuring approval workflows for connection requests • Setting visibility to specific subscriptions • Troubleshooting connectivity issues (check NAT IP configuration and approval status) • Understanding the difference between alias and resource ID for sharing
Watch for These Details: • Connection state must be Approved for traffic to flow • Maximum of 8 NAT IP configurations per Private Link Service • DNS configuration is handled on the consumer side, not the provider side • Private Link Service supports TCP and UDP protocols only
Red Flags in Wrong Answers: • Answers suggesting Basic Load Balancer can be used • Options that route traffic over the public internet • Configurations that require public IP addresses on the consumer side • Answers suggesting Service Endpoints when cross-tenant private access is needed