Quickstart: Create an Azure Firewall and IP Groups - Terraform

In this quickstart, you use Terraform to deploy an Azure Firewall with sample IP Groups used in a network rule and application rule. An IP Group is a top-level resource that allows you to define and group IP addresses, ranges, and subnets into a single object. IP Group is useful for managing IP addresses in Azure Firewall rules. You can either manually enter IP addresses or import them from a file.

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 the sample Terraform code and make it the current directory.

  2. 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"
        }
        azapi = {
          source  = "azure/azapi"
          version = "~>1.5"
        }
      }
    }
    
    provider "azurerm" {
      features {}
    }
    
  3. Create a file named ssh.tf and insert the following code:

    resource "random_pet" "ssh_key_name" {
      prefix    = "ssh"
      separator = ""
    }
    
    resource "azapi_resource_action" "ssh_public_key_gen" {
      type        = "Microsoft.Compute/sshPublicKeys@2022-11-01"
      resource_id = azapi_resource.ssh_public_key.id
      action      = "generateKeyPair"
      method      = "POST"
    
      response_export_values = ["publicKey", "privateKey"]
    }
    
    resource "azapi_resource" "ssh_public_key" {
      type      = "Microsoft.Compute/sshPublicKeys@2022-11-01"
      name      = random_pet.ssh_key_name.id
      location  = azurerm_resource_group.rg.location
      parent_id = azurerm_resource_group.rg.id
    }
    
    output "key_data" {
      value = azapi_resource_action.ssh_public_key_gen.output.publicKey
    }
    
  4. Create a file named main.tf and insert the following code:

    resource "random_pet" "rg_name" {
      prefix = var.resource_group_name_prefix
    }
    
    resource "random_string" "storage_account_name" {
      length  = 8
      lower   = true
      numeric = false
      special = false
      upper   = false
    }
    
    resource "random_password" "password" {
      length      = 20
      min_lower   = 1
      min_upper   = 1
      min_numeric = 1
      min_special = 1
      special     = true
    }
    
    resource "azurerm_resource_group" "rg" {
      name     = random_pet.rg_name.id
      location = var.resource_group_location
    }
    
    resource "azurerm_public_ip" "pip_azfw" {
      name                = "pip-azfw"
      location            = azurerm_resource_group.rg.location
      resource_group_name = azurerm_resource_group.rg.name
      allocation_method   = "Static"
      sku                 = "Standard"
    }
    
    resource "azurerm_storage_account" "sa" {
      name                     = random_string.storage_account_name.result
      resource_group_name      = azurerm_resource_group.rg.name
      location                 = azurerm_resource_group.rg.location
      account_tier             = "Standard"
      account_replication_type = "LRS"
      account_kind             = "StorageV2"
    }
    
    resource "azurerm_firewall_policy" "azfw_policy" {
      name                     = "azfw-policy"
      resource_group_name      = azurerm_resource_group.rg.name
      location                 = azurerm_resource_group.rg.location
      sku                      = var.firewall_sku_tier
      threat_intelligence_mode = "Alert"
    }
    
    resource "azurerm_firewall_policy_rule_collection_group" "prcg" {
      name               = "prcg"
      firewall_policy_id = azurerm_firewall_policy.azfw_policy.id
      priority           = 300
      application_rule_collection {
        name     = "app-rule-collection-1"
        priority = 101
        action   = "Allow"
        rule {
          name = "someAppRule"
          protocols {
            type = "Https"
            port = 443
          }
          destination_fqdns = ["*bing.com"]
          source_ip_groups  = [azurerm_ip_group.ip_group_1.id]
        }
      }
      network_rule_collection {
        name     = "net-rule-collection-1"
        priority = 200
        action   = "Allow"
        rule {
          name                  = "someNetRule"
          protocols             = ["TCP", "UDP", "ICMP"]
          source_ip_groups      = [azurerm_ip_group.ip_group_1.id]
          destination_ip_groups = [azurerm_ip_group.ip_group_2.id]
          destination_ports     = ["90"]
        }
      }
    }
    
    resource "azurerm_firewall" "fw" {
      name                = "azfw"
      location            = azurerm_resource_group.rg.location
      resource_group_name = azurerm_resource_group.rg.name
      sku_name            = "AZFW_VNet"
      sku_tier            = var.firewall_sku_tier
      ip_configuration {
        name                 = "azfw-ipconfig"
        subnet_id            = azurerm_subnet.azfw_subnet.id
        public_ip_address_id = azurerm_public_ip.pip_azfw.id
      }
      firewall_policy_id = azurerm_firewall_policy.azfw_policy.id
    }
    
    resource "azurerm_ip_group" "ip_group_1" {
      name                = "ip-group_1"
      resource_group_name = azurerm_resource_group.rg.name
      location            = azurerm_resource_group.rg.location
      cidrs               = ["13.73.64.64/26", "13.73.208.128/25", "52.126.194.0/23"]
    }
    resource "azurerm_ip_group" "ip_group_2" {
      name                = "ip_group_2"
      resource_group_name = azurerm_resource_group.rg.name
      location            = azurerm_resource_group.rg.location
      cidrs               = ["12.0.0.0/24", "13.9.0.0/24"]
    }
    
    resource "azurerm_virtual_network" "azfw_vnet" {
      name                = "azfw-vnet"
      location            = azurerm_resource_group.rg.location
      resource_group_name = azurerm_resource_group.rg.name
      address_space       = ["10.10.0.0/16"]
    }
    
    resource "azurerm_subnet" "azfw_subnet" {
      name                 = "AzureFirewallSubnet"
      resource_group_name  = azurerm_resource_group.rg.name
      virtual_network_name = azurerm_virtual_network.azfw_vnet.name
      address_prefixes     = ["10.10.0.0/26"]
    }
    
    resource "azurerm_subnet" "server_subnet" {
      name                 = "subnet-server"
      resource_group_name  = azurerm_resource_group.rg.name
      virtual_network_name = azurerm_virtual_network.azfw_vnet.name
      address_prefixes     = ["10.10.1.0/24"]
    }
    
    resource "azurerm_subnet" "jump_subnet" {
      name                 = "subnet-jump"
      resource_group_name  = azurerm_resource_group.rg.name
      virtual_network_name = azurerm_virtual_network.azfw_vnet.name
      address_prefixes     = ["10.10.2.0/24"]
    }
    
    resource "azurerm_public_ip" "vm_jump_pip" {
      name                = "pip-jump"
      location            = azurerm_resource_group.rg.location
      resource_group_name = azurerm_resource_group.rg.name
      allocation_method   = "Static"
      sku                 = "Standard"
    }
    
    resource "azurerm_network_interface" "vm_server_nic" {
      name                = "nic-server"
      location            = azurerm_resource_group.rg.location
      resource_group_name = azurerm_resource_group.rg.name
    
      ip_configuration {
        name                          = "ipconfig-workload"
        subnet_id                     = azurerm_subnet.server_subnet.id
        private_ip_address_allocation = "Dynamic"
      }
    }
    
    resource "azurerm_network_interface" "vm_jump_nic" {
      name                = "nic-jump"
      location            = azurerm_resource_group.rg.location
      resource_group_name = azurerm_resource_group.rg.name
    
      ip_configuration {
        name                          = "ipconfig-jump"
        subnet_id                     = azurerm_subnet.jump_subnet.id
        private_ip_address_allocation = "Dynamic"
        public_ip_address_id          = azurerm_public_ip.vm_jump_pip.id
      }
    }
    
    resource "azurerm_network_security_group" "vm_server_nsg" {
      name                = "nsg-server"
      location            = azurerm_resource_group.rg.location
      resource_group_name = azurerm_resource_group.rg.name
    }
    
    resource "azurerm_network_security_group" "vm_jump_nsg" {
      name                = "nsg-jump"
      location            = azurerm_resource_group.rg.location
      resource_group_name = azurerm_resource_group.rg.name
      security_rule {
        name                       = "Allow-SSH"
        priority                   = 1000
        direction                  = "Inbound"
        access                     = "Allow"
        protocol                   = "Tcp"
        source_port_range          = "*"
        destination_port_range     = "22"
        source_address_prefix      = "*"
        destination_address_prefix = "*"
      }
    }
    
    resource "azurerm_network_interface_security_group_association" "vm_server_nsg_association" {
      network_interface_id      = azurerm_network_interface.vm_server_nic.id
      network_security_group_id = azurerm_network_security_group.vm_server_nsg.id
    }
    
    resource "azurerm_network_interface_security_group_association" "vm_jump_nsg_association" {
      network_interface_id      = azurerm_network_interface.vm_jump_nic.id
      network_security_group_id = azurerm_network_security_group.vm_jump_nsg.id
    }
    
    resource "azurerm_linux_virtual_machine" "vm_server" {
      name                = "server-vm"
      resource_group_name = azurerm_resource_group.rg.name
      location            = azurerm_resource_group.rg.location
      size                = var.virtual_machine_size
      admin_username      = var.admin_username
      admin_ssh_key {
        username   = var.admin_username
        public_key = azapi_resource_action.ssh_public_key_gen.output.publicKey
      }
      network_interface_ids = [azurerm_network_interface.vm_server_nic.id]
      os_disk {
        caching              = "ReadWrite"
        storage_account_type = "Standard_LRS"
      }
      source_image_reference {
        publisher = "Canonical"
        offer     = "UbuntuServer"
        sku       = "18.04-LTS"
        version   = "latest"
      }
      boot_diagnostics {
        storage_account_uri = azurerm_storage_account.sa.primary_blob_endpoint
      }
    }
    
    resource "azurerm_linux_virtual_machine" "vm_jump" {
      name                  = "jump-vm"
      resource_group_name   = azurerm_resource_group.rg.name
      location              = azurerm_resource_group.rg.location
      size                  = var.virtual_machine_size
      network_interface_ids = [azurerm_network_interface.vm_jump_nic.id]
      admin_username        = var.admin_username
      os_disk {
        caching              = "ReadWrite"
        storage_account_type = "Standard_LRS"
      }
      admin_ssh_key {
        username   = var.admin_username
        public_key = azapi_resource_action.ssh_public_key_gen.output.publicKey
      }
      source_image_reference {
        publisher = "Canonical"
        offer     = "UbuntuServer"
        sku       = "18.04-LTS"
        version   = "latest"
      }
      boot_diagnostics {
        storage_account_uri = azurerm_storage_account.sa.primary_blob_endpoint
      }
      computer_name = "JumpBox"
    
    }
    
    resource "azurerm_route_table" "rt" {
      name                          = "rt-azfw-eus"
      location                      = azurerm_resource_group.rg.location
      resource_group_name           = azurerm_resource_group.rg.name
      disable_bgp_route_propagation = false
      route {
        name                   = "azfwDefaultRoute"
        address_prefix         = "0.0.0.0/0"
        next_hop_type          = "VirtualAppliance"
        next_hop_in_ip_address = azurerm_firewall.fw.ip_configuration[0].private_ip_address
      }
    }
    
    resource "azurerm_subnet_route_table_association" "server_subnet_rt_association" {
      subnet_id      = azurerm_subnet.server_subnet.id
      route_table_id = azurerm_route_table.rt.id
    }
    
  5. 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 for the Resource Group Name that's combined with a random id so name is unique in your Azure subcription."
      default     = "rg"
    }
    
    variable "firewall_sku_tier" {
      type        = string
      description = "Firewall SKU."
      default     = "Premium" # Valid values are Standard and Premium
      validation {
        condition     = contains(["Standard", "Premium"], var.firewall_sku_tier)
        error_message = "The SKU must be one of the following: Standard, Premium"
      }
    }
    
    variable "virtual_machine_size" {
      type        = string
      description = "Size of the virtual machine."
      default     = "Standard_D2_v3"
    }
    
    variable "admin_username" {
      type        = string
      description = "Value of the admin username."
      default     = "azureuser"
    }
    
  6. Create a file named outputs.tf and insert the following code:

    output "resource_group_name" {
      value = azurerm_resource_group.rg.name
    }
    
    output "firewall_name" {
      value = azurerm_firewall.fw.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. Run az network ip-group list to display the two new IP Groups.

    az network ip-group list --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