Azure Private Link

About Azure Private Link

Azure Private Link is Microsoft Azure's private connectivity service for reaching supported Azure platform services, partner offerings, and customer-owned services through private IP addresses instead of exposing those service endpoints to the public internet. Its main building block is a private endpoint, which places a network interface with a private IP address inside a virtual network and maps that address to a supported Private Link resource. Private Link is most useful when an organization wants PaaS access to stay on the Microsoft backbone while preserving familiar Azure service models such as Storage, SQL Database, Key Vault, App Service, and other supported services.

What is Azure Private Link used for?

Azure Private Link is used when applications, administrators, or connected networks need private access to Azure services that would otherwise be reached through public service endpoints. A private endpoint gives the selected service a private IP address in a virtual network, so workloads can connect through private network paths while the service itself remains managed by Azure.

Common designs include privately connecting an application subnet to Azure Storage or Azure SQL Database, exposing a provider-owned application privately to customer virtual networks, and extending access from on-premises networks through VPN or ExpressRoute. Private Link does not replace the application service, firewall rules, identity controls, or DNS design. It changes how the service is reached and is therefore one part of a broader network and security architecture.

How do private endpoints work?

A private endpoint is a network interface that Azure creates inside the customer's virtual network. It receives a private IP address from the selected subnet and maps that address to a supported Private Link resource. Microsoft documents that the private endpoint must be deployed in the same region and subscription as the virtual network, while the target Private Link resource can be in another region.

The private IP remains associated with the private endpoint for its lifecycle. Multiple private endpoints can point to the same service when separate networks, subscriptions, or environments need isolated connections. However, Microsoft recommends avoiding unnecessary duplicate endpoints in a network that shares the same DNS configuration because duplicate DNS entries and conflicting resolution can make private connectivity harder to operate.

Why is DNS important with Azure Private Link?

Private Link deployments depend heavily on name resolution. Applications usually continue to connect to the service's normal fully qualified domain name, but DNS must resolve that name to the private endpoint address from networks that should use the private path. Microsoft publishes private DNS zone names for services that support private endpoints, and Azure Private DNS is commonly used to host those records.

This makes DNS design one of the biggest operational differences between a simple proof of concept and a production deployment. Hub-and-spoke environments, hybrid networks, custom DNS servers, multiple Azure regions, and split-horizon requirements can all affect how names are resolved. A private endpoint can be technically healthy while an application still fails because its DNS query returns the public endpoint instead of the private IP.

How is Private Link different from service endpoints?

Both Private Link and virtual network service endpoints help restrict access to Azure services, but they work differently. A service endpoint extends the identity of a virtual network subnet to a supported Azure service while clients still address the service through its public endpoint. Private Link instead places a private endpoint with a private IP inside the virtual network.

Microsoft currently recommends Private Link and private endpoints for secure private access to services hosted on Azure. Service endpoints can still be useful in simpler or large-scale designs where subnet identity and service firewall rules meet the requirement without the additional private endpoint and DNS architecture. Buyers should choose based on isolation, network topology, DNS complexity, supported-service behavior, and cost rather than treating one model as automatically superior for every workload.

What is Azure Private Link Service?

Private Link Service is the provider-side feature for publishing a customer-owned or partner-owned service privately to consumers. In the standard design, the provider places the service behind an Azure Standard Load Balancer and creates a Private Link Service that references the load balancer frontend. Consumers then create private endpoints in their own virtual networks and request connections to that service.

The provider can control service visibility and approve or reject connection requests. Microsoft documents a globally unique alias that can be shared with consumers, and providers can use auto-approval for selected subscriptions. Standard Private Link Service currently supports IPv4 and TCP or UDP traffic, requires Standard Load Balancer for the standard deployment model, and has provider-side networking considerations such as NAT IP capacity and TCP Proxy v2 behavior.

How is Azure Private Link priced?

Pricing was checked against Microsoft's current Azure Private Link pricing page on August 26, 2026. Microsoft does not present one flat product subscription price. Private endpoints are billed by the time they exist, and inbound and outbound data processed through Private Link are additional usage meters. Normal Azure data transfer charges can also apply depending on the traffic path.

Microsoft currently lists no charge for creating a Private Link Service itself, but the infrastructure behind that service, including Standard Load Balancer and the provider's compute and networking resources, can still have their own charges. This means cost estimation should include endpoint count, endpoint lifetime, traffic direction and volume, regional data movement, and the underlying Azure service rather than looking only at the Private Link line item.

What are the main limitations and design tradeoffs?

Private Link improves network isolation, but it adds components that must be governed. Teams need private endpoint lifecycle management, DNS zones and links, approval workflows, address-space planning, monitoring, and documentation of which resources are reachable from which networks. Large estates can accumulate hundreds of private endpoints if every team creates its own copy without a shared architecture.

Private Link also does not automatically disable the public endpoint of the target service. Many Azure services have a separate setting or firewall configuration that controls public access, so buyers should verify each service's behavior instead of assuming the private endpoint alone closes the public path. Service support and region availability should also be checked before standardizing on Private Link because not every Azure capability exposes identical private endpoint options.

Who should choose something else?

Teams should consider alternatives when the requirement is simpler than full private endpoint connectivity. Service endpoints may be adequate when subnet-based service restrictions are enough and the organization wants to avoid private endpoint DNS and lifecycle overhead. Application Gateway, Front Door, Load Balancer, VPN, ExpressRoute, Bastion, and Azure Firewall solve different network problems and should not be substituted for Private Link solely because they also improve network security or connectivity.

Private Link is a stronger fit when supported PaaS or provider services must appear through private IP addresses inside controlled virtual networks, especially for regulated, enterprise, hybrid, or segmented architectures. Organizations should still combine it with identity, service firewall settings, DNS governance, logging, and application-level security rather than treating private routing as a complete security control.