Azure Private Link: A Guide to Secure Connectivity

Azure Private Link is a game-changer for secure connectivity. It allows you to create private endpoints for your Azure resources, enabling you to access them from a virtual network without exposing them to the public internet.

This means you can keep your resources safe from unauthorized access, which is especially important for sensitive data. Azure Private Link helps you meet compliance and security requirements by providing a secure connection.

With Azure Private Link, you can connect to Azure services like Azure Storage, Azure SQL Database, and Azure Cosmos DB. This allows you to use these services without exposing them to the public internet, which reduces the attack surface.

By using Azure Private Link, you can also enable secure connectivity for your on-premises resources. This is done by creating a private endpoint in your virtual network, which allows you to access your on-premises resources from Azure services.

Azure Private Link is a service that enables you to securely access Azure services over a private connection within your virtual network.

Azure Private Link allows you to access Azure services such as Azure Storage, Azure SQL Database, and more, while keeping your resources isolated from the public internet.

Azure Private Link works by creating a private connection between your virtual network and the Azure service you want to access.

You can use Azure Private Link to connect to Azure PaaS services that support Private Link or to your own Private Link Service.

Azure Private Link Service is a service created by a service provider, and it can be attached to the frontend IP configuration of a Standard Load Balancer.

Here are the key components of Azure Private Link:

Azure Private Link is a powerful tool that allows you to bring Azure services into your private virtual network, or deliver your own services to your customers' virtual networks. This is done by mapping a service to a private endpoint, eliminating the need for gateways, NAT devices, ExpressRoute, or VPN connections.

To get started with Azure Private Link, you'll need to set up a Private Link Service on the Azure service you want to access privately. This is the first step in the process.

Here are the key steps to follow:

A private endpoint is a network interface that connects to the service over a private link, and it's assigned a private IP address from your virtual network. This is a critical component of Azure Private Link.

Azure Private Link offers a robust security and compliance solution. By carrying traffic privately, your data isn't exposed to the internet, reducing your exposure to threats.

Private Link maps your service to Azure virtual networks through a private endpoint, helping you meet compliance standards. This is a game-changer for businesses that handle sensitive data.

You only pay for private endpoint resource hours and the data processed through your private endpoint. This means you can enjoy enhanced security without breaking the bank.

Using Private Link also protects Azure services against data exfiltration. By mapping private endpoints to Azure PaaS resources, you eliminate the threat of data exfiltration in the event of a security incident.

Here are the benefits of using Private Link for security and compliance:

Private Link simplifies the way you consume services on Azure, allowing you to privately consume Azure PaaS, Microsoft partner, and your own services in your virtual networks.

To create a Private Link Service, your service backends should be in a Virtual Network and behind a Standard Load Balancer. This is a crucial step in setting up Private Link.

You can create Private Endpoints using the Azure portal, PowerShell, or the Azure CLI. This gives you flexibility in how you set up and manage your Private Link services.

Private Endpoints can be created using the following methods:

You can have multiple Private Endpoints in the same VNet or subnet, and they can connect to different services. This is a convenient feature that allows for flexibility in your network configuration.

Private Endpoints can connect to Private Link services or Azure PaaS across Microsoft Entra tenants. However, this requires a manual request approval process.

To control the exposure of your Private Link Service, you can use the visibility configuration on Private Link service. This allows you to set the visibility to None, Restrictive, or All.

The visibility configuration has three settings: None, Restrictive, and All. Here's a brief description of each:

After creating a Private Endpoint, the SQL admin can manage the Private Endpoint Connection to SQL Database. This involves navigating to the server resource in the Azure portal and approving or rejecting the Private Endpoint Connection request.

To set up Private Link, you'll need to start by disabling network policies for Private Link Service. This is a crucial step, as Private Link Service needs to disable network policies to function properly.

You can choose any subnet in your VNet where your service is deployed, and you don't require a dedicated subnet for Private Endpoints. This means you have flexibility in designing your network architecture.

To simplify the way you consume services on Azure, Private Link works across Microsoft Entra ID (formerly Azure Active Directory) tenants to help unify your experience across services.

You can have multiple Private Endpoints in the same VNet or subnet, and they can connect to different services. This allows for scalability and flexibility in your setup.

Azure Private Link provides the functionality of non-overlapping address space with your customer's address space, so you don't need to worry about that.

To test connectivity to SQL Database from an Azure VM in the same virtual network, start by connecting to the virtual machine via Remote Desktop (RDP) session. Then, use PowerShell command to check the connectivity.

To set up Private Link, you'll need to use the Fully Qualified Domain Name (FQDN) of the server in connection strings for your clients. This is because any login attempts made directly to the IP address or using the private link FQDN shall fail.

Here's a step-by-step guide to creating a Private Link Service:

You can't modify a Private Endpoint Network Interface Card (NIC) once it's assigned to a private endpoint. It remains read-only for the life cycle of the Private endpoint.

The NIC is assigned when a private endpoint is created and will stay that way until the endpoint is no longer needed.

To create a Private Link Service, your service backends should be in a Virtual Network and behind a Standard Load Balancer. This is a crucial step in getting started with Private Link.

You can scale your Private Link Service in a few different ways, including adding Backend VMs to the pool behind your Standard Load Balancer, adding an IP to the Private Link Service, or adding new Private Link Service to Standard Load Balancer.

Here are some key scaling options for your Private Link Service:

To create a Private Link service, you'll need to ensure your service backends are in a Virtual Network and behind a Standard Load Balancer. This is a requirement for creating a Private Link Service, as specified in Example 5.

Your service backends should be in a Virtual Network and behind a Standard Load Balancer.

You can't create a Private Link service with a Basic Load Balancer, so make sure you're using the correct type of load balancer. This is a limitation that's outlined in Example 7.

If you're planning to create a Private Link service, you'll need to consider scaling it in the future. You can scale your Private Link Service in a few different ways, as outlined in Example 6.

Here are the ways you can scale your Private Link Service:

To scale your Private Link Service, you can either add new NAT IPs or add more VMs behind the Standard Load Balancer. This will increase the port availability and allow for more connections. Connections will be distributed across NAT IPs and VMs behind the Standard Load Balancer.

PolyBase and the COPY statement are commonly used to load data into Azure Synapse Analytics from Azure Storage accounts. This is a reliable method for transferring data, but it has limitations when it comes to accessing secured storage accounts.

If the Azure Storage account limits access to a set of virtual network subnets via Private Endpoints, Service Endpoints, or IP-based firewalls, connectivity from PolyBase and the COPY statement will break. This can be a major issue for import and export scenarios.

To enable both import and export scenarios with Azure Synapse Analytics connecting to Azure Storage that's secured to a virtual network, follow the steps provided. This will ensure that your data transfer is secure and reliable.