Quickstart: Use Terraform to deploy Azure Bastion

In this Quickstart, you learn how to use Terraform to deploy Azure Bastion automatically in the Azure portal. To do this, you create an Azure Bastion host and its corresponding Azure resources, which include a resource group, virtual network, Azure Bastion subnet, and a public IP. This setup ensures a secure, private network environment for your Azure services. The following diagram provides an overview of Azure Bastion deployments:

Diagram that shows the Azure Bastion architecture.

Deploying Azure Bastion allows you to use RDP and SSH to access to your virtual machines within the Azure portal. This service is provisioned directly in your virtual network and supports all virtual machines there, reducing exposure to public network connections. When you deploy Bastion automatically, Bastion is deployed with the Standard SKU. See the Azure Bastion deployment guidance for more information about how to customize your Azure Bastion deployment.

Terraform enables the definition, preview, and deployment of cloud infrastructure. Using Terraform, you create configuration files using HCL syntax. The HCL syntax allows you to specify the cloud provider - such as Azure - and the elements that make up your cloud infrastructure. After you create your configuration files, you create an execution plan that allows you to preview your infrastructure changes before they're deployed. Once you verify the changes, you apply the execution plan to deploy the infrastructure.

  • Create an Azure resource group with a unique name.
  • Establish a virtual network with a specified name and address.
  • Set up a subnet specifically for Azure Bastion within the created virtual network.
  • Allocate a static, standard public IP for Azure Bastion within the resource group.
  • Construct an Azure Bastion host with a specified IP configuration within the resource group.
  • Output the names and IP address of the resource group, plus the Azure Bastion host.

Prerequisites

Implement the Terraform code

Note

The sample code for this article is located in the Azure Terraform GitHub repo. You can view the log file containing the test results from current and previous versions of Terraform.

See more articles and sample code showing how to use Terraform to manage Azure resources.

  1. Create a directory in which to test and run the sample Terraform code, and make it the current directory.

  2. Create a file named main.tf, and insert the following code:

    # Create Resource Group
    resource "random_pet" "rg_name" {
      prefix = var.resource_group_name_prefix
    }
    
    resource "azurerm_resource_group" "rg" {
      location = var.resource_group_location
      name     = random_pet.rg_name.id
    }
    
    # Create Virtual Network
    resource "azurerm_virtual_network" "vnet" {
      name                = "example-network"
      address_space       = ["10.0.0.0/16"]
      location            = azurerm_resource_group.rg.location
      resource_group_name = azurerm_resource_group.rg.name
    }
    
    # Create Subnet for Azure Bastion
    resource "azurerm_subnet" "bastion_subnet" {
      name                 = "AzureBastionSubnet"
      resource_group_name  = azurerm_resource_group.rg.name
      virtual_network_name = azurerm_virtual_network.vnet.name
      address_prefixes     = ["10.0.1.0/24"]
    }
    
    # Create Public IP for Azure Bastion
    resource "azurerm_public_ip" "bastion_pip" {
      name                = "example-pip"
      location            = azurerm_resource_group.rg.location
      resource_group_name = azurerm_resource_group.rg.name
      allocation_method   = "Static"
      sku                 = "Standard"
    }
    
    # Create Azure Bastion Host
    resource "azurerm_bastion_host" "bastion" {
      name                = "example-bastion"
      location            = azurerm_resource_group.rg.location
      resource_group_name = azurerm_resource_group.rg.name
    
      ip_configuration {
        name                 = "configuration"
        subnet_id            = azurerm_subnet.bastion_subnet.id
        public_ip_address_id = azurerm_public_ip.bastion_pip.id
      }
    }
    
  3. Create a file named outputs.tf, and insert the following code:

    output "resource_group_name" {
      value = azurerm_resource_group.rg.name
    }
    
    output "bastion_host_name" {
      value = azurerm_bastion_host.bastion.name
    }
    
    output "bastion_host_ip" {
      value = azurerm_public_ip.bastion_pip.ip_address
    }
    
  4. Create a file named providers.tf, and insert the following code:

    terraform {
      required_providers {
        azurerm = {
          source  = "hashicorp/azurerm"
          version = "~>3.0"
        }
        random = {
          source  = "hashicorp/random"
          version = "~>3.0"
        }
      }
    }
    
    provider "azurerm" {
      features {}
    }
    
  5. Create a file named variables.tf, and insert the following code:

    variable "resource_group_location" {
      type        = string
      default     = "chinaeast2"
      description = "Location of the resource group."
    }
    
    variable "resource_group_name_prefix" {
      type        = string
      default     = "rg"
      description = "Prefix of the resource group name that's combined with a random ID so name is unique in your Azure subscription."
    }
    

Initialize Terraform

Run terraform init to initialize the Terraform deployment. This command downloads the Azure provider required to manage your Azure resources.

terraform init -upgrade

Key points:

  • The -upgrade parameter upgrades the necessary provider plugins to the newest version that complies with the configuration's version constraints.

Create a Terraform execution plan

Run terraform plan to create an execution plan.

terraform plan -out main.tfplan

Key points:

  • The terraform plan command creates an execution plan, but doesn't execute it. Instead, it determines what actions are necessary to create the configuration specified in your configuration files. This pattern allows you to verify whether the execution plan matches your expectations before making any changes to actual resources.
  • The optional -out parameter allows you to specify an output file for the plan. Using the -out parameter ensures that the plan you reviewed is exactly what is applied.

Apply a Terraform execution plan

Run terraform apply to apply the execution plan to your cloud infrastructure.

terraform apply main.tfplan

Key points:

  • The example terraform apply command assumes you previously ran terraform plan -out main.tfplan.
  • If you specified a different filename for the -out parameter, use that same filename in the call to terraform apply.
  • If you didn't use the -out parameter, call terraform apply without any parameters.

Verify the results

  1. Get the Azure resource group name.

    resource_group_name=$(terraform output -raw resource_group_name)
    
  2. Get the Azure Bastion host name.

    bastion_host_name=$(terraform output -raw bastion_host_name)
    
  3. Get the Azure Bastion host ip address.

    bastion_host_ip=$(terraform output -raw bastion_host_ip)
    
  4. Run az network bastion show to view the Azure Bastion host.

    az network bastion show --name $bastion_host_name --resource-group $resource_group_name
    

Clean up resources

When you no longer need the resources created via Terraform, do the following steps:

  1. Run terraform plan and specify the destroy flag.

    terraform plan -destroy -out main.destroy.tfplan
    

    Key points:

    • The terraform plan command creates an execution plan, but doesn't execute it. Instead, it determines what actions are necessary to create the configuration specified in your configuration files. This pattern allows you to verify whether the execution plan matches your expectations before making any changes to actual resources.
    • The optional -out parameter allows you to specify an output file for the plan. Using the -out parameter ensures that the plan you reviewed is exactly what is applied.
  2. Run terraform apply to apply the execution plan.

    terraform apply main.destroy.tfplan
    

Troubleshoot Terraform on Azure

Troubleshoot common problems when using Terraform on Azure.

Next steps

In this quickstart, you used Terraform to create an Azure resource group and other complimentary Azure resources to set up an Azure Bastion host. Next, you can explore the following resources to learn more about Azure Bastion and Terraform.