Azure Private Link Documentation

Azure Private Link Usage Scenarios

Azure Private Link provides a secure and private connection to Azure services and customer-owned services hosted on Azure. Here are some common usage scenarios:

1. Accessing Azure PaaS Services Privately

This is the most common use case. You can secure access to services like Azure Storage, Azure SQL Database, Azure Cosmos DB, Azure Key Vault, and Azure Databricks by creating a Private Endpoint within your virtual network. This eliminates the need to expose these services to the public internet.

Example: Connecting to Azure Storage

To connect to an Azure Storage account using Private Link, you would:

1. Create a Private Endpoint in your virtual network, targeting the Azure Storage account.
2. Configure your application or virtual machines within the virtual network to use the private IP address of the Private Endpoint.
3. Ensure your DNS resolution is configured to map the storage account's FQDN to the private IP address.

2. Connecting to Your Own Services Hosted on Azure

If you have applications deployed on Azure Virtual Machines, Azure Kubernetes Service (AKS), or App Services, you can make them accessible privately to other virtual networks or on-premises environments using Azure Private Link. This involves creating a Private Link Service.

Steps for Creating a Private Link Service:

• Deploy your service behind an internal Azure Load Balancer in a virtual network.
• Create a Private Link Service that points to the frontend IP configuration of your internal Load Balancer.
• Consumers of your service can then create Private Endpoints to connect to your Private Link Service.

3. Hybrid Connectivity (On-Premises to Azure Services)

Azure Private Link facilitates secure connectivity from your on-premises networks to Azure PaaS services. By combining Azure VPN Gateway or Azure ExpressRoute with Private Link, you can route traffic from your on-premises environment through a private connection to your Azure resources, bypassing the public internet.

4. Inter-VNet Communication with Enhanced Security

While VNet peering is common for inter-VNet communication, Private Link can offer an additional layer of security and control. You can use Private Endpoints to connect services residing in one VNet to consumers in another VNet, ensuring traffic stays within the Azure backbone and is not exposed publicly.

5. Connecting to Third-Party Services via Marketplace

Many third-party SaaS providers offer their services through Azure Marketplace, and they can integrate with Azure Private Link. This allows you to consume these partner services privately, similar to how you would consume native Azure services.

Example: Connecting to a Partner's Data Analytics Platform

• The partner exposes their service via a Private Link Service.
• You create a Private Endpoint in your VNet to connect to the partner's Private Link Service.
• Your applications can then access the partner's data platform securely.

Key Considerations for Usage:

• Network Security Groups (NSGs): Ensure NSGs associated with the subnet of your Private Endpoint allow traffic from your application subnets.
• Firewall Rules: For services like Azure SQL Database, ensure that your service's firewall rules are configured to allow connections from the private IP address of your Private Endpoint.
• DNS Resolution: Correctly configuring DNS is crucial for Private Link to work. Private Endpoints are assigned private IP addresses, and your applications need to resolve the service's FQDN to these private IPs.
• Service Limits: Be aware of the limits on the number of Private Endpoints and Private Link Services you can create per subscription.