Azure Private Link Documentation

Introduction to Azure Private Link

Azure Private Link provides the ultimate connectivity solution by enabling you to access Azure Platform as a Service (PaaS) and Azure Virtual Machines (VMs) over a private endpoint within your virtual network. Traffic between your virtual network and the service travels the Microsoft backbone network, eliminating exposure to the public internet.

This service simplifies network security and helps you meet compliance requirements by ensuring that data doesn't traverse public networks. Private Link is supported across a wide range of Azure services, including Azure Storage, Azure SQL Database, Azure Key Vault, and many others.

How Azure Private Link Works

Azure Private Link utilizes private endpoints to establish a private connection to an Azure service. A private endpoint is a network interface that connects your virtual network privately and securely to a specific Azure service.

Service Provider: An Azure service (e.g., Azure Storage) exposes its resources via a private link service.
Private Endpoint Creation: You create a private endpoint in your virtual network, specifying the Azure service you want to connect to.
Network Integration: Azure assigns a private IP address from your virtual network to the private endpoint.
Traffic Routing: DNS is configured to resolve the service's FQDN (Fully Qualified Domain Name) to the private IP address of the private endpoint.
Secure Connectivity: All traffic destined for the Azure service is routed through the Microsoft backbone network to the private endpoint, bypassing the public internet.

Important: For Azure PaaS services, Private Link uses the service's standard FQDN. For your own services or partner services, you'll use a custom domain.

Key Concepts

Private Endpoint

A network interface that connects your virtual network privately and securely to an Azure service. It gets a private IP address from your virtual network.

Private Link Service

A service that allows you to expose your own Azure service or a partner service through Private Link, making it accessible privately from other virtual networks.

Private Endpoint Connection

Represents the connection from a private endpoint to a private link service. It can be in a 'Pending', 'Approved', 'Rejected', or 'Disconnected' state.

Network Security Groups (NSGs)

NSGs can be applied to the subnet containing the private endpoint to further control inbound and outbound traffic.

Common Use Cases

Securing Access to Azure PaaS: Connect to Azure Storage, Azure SQL Database, Azure Cosmos DB, Azure Key Vault, and more, without exposing them to the public internet.
Connecting to Customer-Owned Services: Allow other Azure virtual networks or on-premises networks to securely access your applications hosted in Azure.
Partner Service Integration: Enable secure, private access to SaaS offerings from partners.
Hybrid Cloud Connectivity: Extend your on-premises network to Azure services privately and securely.

Benefits of Azure Private Link

Enhanced Security: Eliminates public internet exposure, reducing the attack surface.
Simplified Network Architecture: Reduces the need for complex VPNs or ExpressRoute circuits for accessing Azure services.
Compliance: Helps meet strict regulatory and compliance requirements by keeping traffic within the Microsoft backbone.
Consistent Connectivity: Provides a unified experience for connecting to both Azure PaaS and your own services.
Performance: Traffic stays on the Microsoft backbone, potentially offering lower latency and higher throughput.

Getting Started with Azure Private Link

Creating a private endpoint is a straightforward process managed through the Azure portal, Azure CLI, or PowerShell.

Using Azure Portal:

Navigate to your desired Azure service (e.g., Storage account).
Under 'Settings', select 'Networking'.
Go to the 'Private endpoint connections' tab and click '+ Private endpoint'.
Configure the basic details, resource, and virtual network for your private endpoint.
Azure will guide you through the DNS configuration.

Example using Azure CLI:

az network private-endpoint create \
    --name myPrivateEndpoint \
    --resource-group myResourceGroup \
    --vnet-name myVNet \
    --subnet mySubnet \
    --private-connection-resource-id "/subscriptions/00000000-0000-0000-0000-000000000000/resourceGroups/myResourceGroup/providers/Microsoft.Storage/storageAccounts/mystorageaccount" \
    --group-ids "blob" \
    --connection-name myConnection

For detailed steps and specific service configurations, please refer to the official Azure Private Link documentation.

Advanced Topics

Private Link Service Configuration: Learn how to create and manage your own private link services for exposing your applications.
Private DNS Integration: Understand how to configure Azure Private DNS Zones for seamless resolution of private endpoint connections.
Cross-region and Cross-subscription Connectivity: Explore scenarios for connecting across different Azure regions and subscriptions.
Troubleshooting Private Endpoints: Common issues and solutions for connectivity problems.