Private Endpoints in Azure provide secure and private connectivity to Azure services from within your virtual network. They enable you to access certain Azure services privately without going over the public internet. This helps enhance the security and compliance of your applications and data by keeping traffic within the boundaries of your virtual network.

Here's an overview of Private Endpoints and how they work:

1. What is a Private Endpoint? A Private Endpoint is an interface in your virtual network that connects to a specific instance of an Azure service, such as Azure Storage, Azure SQL Database, or Azure Cosmos DB. It is assigned a private IP address from your virtual network's address space. When you use a Private Endpoint to connect to an Azure service, the traffic stays within your virtual network and does not traverse the public internet.

2. How Private Endpoints Work: When you create a Private Endpoint, Azure creates a network interface in your virtual network and associates it with the specified Azure service. The network interface is assigned a private IP address from the subnet within your virtual network.

   When your application communicates with the Azure service through the Private Endpoint, the traffic is routed internally within the Azure backbone network, ensuring that it remains isolated from the public internet.

3. Benefits of Private Endpoints:

   • Enhanced security: Private Endpoints help secure data access by avoiding exposure to the public internet and eliminating the need for public IP addresses on the service.

   • Compliance: They can assist in meeting regulatory and compliance requirements by keeping data within specific network boundaries.

   • Reduced network egress charges: Since traffic doesn't leave the Azure backbone, egress data transfer charges are avoided.

4. Services with Private Endpoint Support: Microsoft continues to expand the number of services that support Private Endpoints. services like Azure Storage, Azure SQL Database, Azure Cosmos DB, Azure App Service Environment, and more support Private Endpoints.

5. Creating a Private Endpoint: To create a Private Endpoint, you need to define a subnet in your virtual network and then create the Private Endpoint resource, associating it with the target Azure service.

Example Terraform configuration for creating an Azure Private Endpoint to connect to an Azure Storage Account:

provider "azurerm" {
  features {}
}

resource "azurerm_resource_group" "example" {
  name     = "my-resource-group"
  location = "East US"
}

resource "azurerm_virtual_network" "example" {
  name                = "my-virtual-network"
  address_space       = ["10.0.0.0/16"]
  location            = azurerm_resource_group.example.location
  resource_group_name = azurerm_resource_group.example.name
}

resource "azurerm_subnet" "example" {
  name                 = "my-subnet"
  resource_group_name  = azurerm_resource_group.example.name
  virtual_network_name = azurerm_virtual_network.example.name
  address_prefix       = "10.0.1.0/24"
}

resource "azurerm_storage_account" "example" {
  name                     = "mystorageaccount"
  resource_group_name      = azurerm_resource_group.example.name
  location                 = azurerm_resource_group.example.location
  account_tier             = "Standard"
  account_replication_type = "LRS"
}

resource "azurerm_private_endpoint" "example" {
  name                = "my-private-endpoint"
  location            = azurerm_resource_group.example.location
  resource_group_name = azurerm_resource_group.example.name
  subnet_id           = azurerm_subnet.example.id

  private_service_connection {
    name                           = "my-private-connection"
    private_connection_resource_id = azurerm_storage_account.example.id
    is_manual_connection           = false
    subresource_names              = ["blob"]
  }
}