Quickstart: Create a Windows VM cluster in Azure using Terraform

Applies to: ✔️ Windows VMs

This article shows you how to create a Windows VM cluster (containing three Windows VM instances) in Azure using Terraform.

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 the sample Terraform code and make it the current directory.

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

    terraform {
      required_version = ">=1.0"
      required_providers {
        azurerm = {
          source  = "hashicorp/azurerm"
          version = "~>3.0"
        }
        random = {
          source  = "hashicorp/random"
          version = "~>3.0"
        }
      }
    }
    provider "azurerm" {
      features {}
    }
    
  3. Create a file named main.tf and insert the following code:

    resource "random_pet" "rg_name" {
      prefix = var.resource_group_name_prefix
    }
    
    resource "azurerm_resource_group" "rg" {
      name     = random_pet.rg_name.id
      location = var.resource_group_location
    }
    
    resource "random_string" "windows_server_vm_hostname" {
      length  = 8
      lower   = true
      upper   = false
      special = false
    }
    
    resource "random_pet" "windows_server_public_ip_dns" {
      prefix = "dns"
    }
    
    resource "random_password" "password" {
      length  = 16
      special = true
      lower   = true
      upper   = true
      numeric = true
    }
    
    # The following module is a Terraform Verified Module. 
    # For more information about Verified Modules, see 
    # https://github.com/azure/terraform-azure-modules/
    module "windows_server" {
      count                         = 3 # Define 3 Windows Server VMs
      source                        = "Azure/compute/azurerm"
      resource_group_name           = azurerm_resource_group.rg.name
      vnet_subnet_id                = module.network.vnet_subnets[0]
      is_windows_image              = true
      vm_hostname                   = "vm-${random_string.windows_server_vm_hostname.result}-${count.index}"
      delete_os_disk_on_termination = true
      admin_password                = random_password.password.result
      vm_os_simple                  = "WindowsServer"
      public_ip_dns                 = ["${random_pet.windows_server_public_ip_dns.id}-${count.index}"]
    }
    
    # The following module is a Terraform Verified Module. 
    # For more information about Verified Modules, see 
    # https://github.com/azure/terraform-azure-modules/
    module "network" {
      source              = "Azure/network/azurerm"
      resource_group_name = azurerm_resource_group.rg.name
      version             = "5.2.0"
      subnet_prefixes     = ["10.0.1.0/24"]
      subnet_names        = ["subnet1"]
      use_for_each        = true
    }
    
  4. Create a file named variables.tf and insert the following code:

    variable "resource_group_location" {
      type        = string
      default     = "eastus"
      description = "Location for all resources."
    }
    
    variable "resource_group_name_prefix" {
      type        = string
      default     = "rg"
      description = "Prefix of the resource group name that's combined with a random value so name is unique in your Azure subscription."
    }
    
  5. Create a file named outputs.tf and insert the following code:

    output "resource_group_name" {
      value = azurerm_resource_group.rg.name
    }
    
    output "windows_vm_public_names" {
      value = module.windows_server[*].public_ip_dns_name
    }
    
    output "vm_public_ip_addresses" {
      value = module.windows_server[*].public_ip_address
    }
    
    output "vm_private_ip_addresses" {
      value = module.windows_server[*].network_interface_private_ip
    }
    
    output "vm_hostnames" {
      value = module.windows_server[*].vm_names
    }
    

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.

Cost information isn't presented during the virtual machine creation process for Terraform like it is for the Azure portal. If you want to learn more about how cost works for virtual machines, see the Cost optimization Overview page.

Verify the results

  1. Get the Azure resource group name.

    resource_group_name=$(terraform output -raw resource_group_name)
    
  2. Run az vm list with a JMESPath query to display the names of the virtual machines created in the resource group.

    az vm list \
      --resource-group $resource_group_name \
      --query "[].{\"VM Name\":name}" -o table
    

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