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

• Install and configure Terraform

Implement the Terraform code

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

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