QuickStart: Create and configure Azure DDoS Network Protection using Terraform

This QuickStart describes how to use Terraform to create and enable a distributed denial of service (DDoS) protection plan and Azure virtual network (VNet). An Azure DDoS Network Protection plan defines a set of virtual networks that have DDoS protection enabled across subscriptions. You can configure one DDoS protection plan for your organization and link virtual networks from multiple subscriptions to the same plan.

Diagram of DDoS Network Protection.

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.

In this article, you learn how to:

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 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" "ddos_protection_plan" {
      length  = 13
      upper   = false
      numeric = false
      special = false
    }
    
    resource "azurerm_network_ddos_protection_plan" "ddos" {
      name                = random_string.ddos_protection_plan.result
      resource_group_name = azurerm_resource_group.rg.name
      location            = azurerm_resource_group.rg.location
    }
    
    resource "random_string" "virtual_network_name" {
      length  = 13
      upper   = false
      numeric = false
      special = false
    }
    
    resource "azurerm_virtual_network" "vnet" {
      name                = random_string.virtual_network_name.result
      resource_group_name = azurerm_resource_group.rg.name
      location            = azurerm_resource_group.rg.location
      address_space       = [var.vnet_address_prefix]
    
      subnet {
        name           = "default"
        address_prefix = var.subnet_prefix
      }
      ddos_protection_plan {
        id     = azurerm_network_ddos_protection_plan.ddos.id
        enable = var.ddos_protection_plan_enabled
      }
    }
    
  4. Create a file named variables.tf and insert the following code:

    variable "resource_group_location" {
      type        = string
      description = "Location for all resources."
      default     = "eastus"
    }
    
    variable "resource_group_name_prefix" {
      type        = string
      description = "Prefix of the resource group name that's combined with a random ID so name is unique in your Azure subscription."
      default     = "rg"
    }
    
    variable "vnet_address_prefix" {
      type        = string
      description = "Specify the virtual network address prefix"
      default     = "172.17.0.0/16"
    }
    
    variable "subnet_prefix" {
      type        = string
      description = "Specify the virtual network subnet prefix"
      default     = "172.17.0.0/24"
    }
    
    variable "ddos_protection_plan_enabled" {
      type        = bool
      description = "Enable DDoS protection plan."
      default     = true
    }
    
  5. Create a file named outputs.tf and insert the following code:

    output "resource_group_name" {
      value = azurerm_resource_group.rg.name
    }
    
    output "ddos_protection_plan_name" {
      value = azurerm_network_ddos_protection_plan.ddos.name
    }
    
    output "virtual_network_name" {
      value = azurerm_virtual_network.vnet.name
    }
    

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 DDoS protection plan name.

    ddos_protection_plan_name=$(terraform output -raw ddos_protection_plan_name)
    
  3. Run az network ddos-protection show to display information about the new DDoS protection plan.

    az network ddos-protection show \
        --resource-group $resource_group_name \
        --name $ddos_protection_plan_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