Quickstart: Create an Azure DNS zone and record using Terraform

This article shows how to use Terraform to create an Azure DNS zone and an A record in that zone.

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

  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 = ">=1.2"
      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" "azurerm_dns_zone_name" {
      length  = 13
      lower   = true
      numeric = false
      special = false
      upper   = false
    }
    
    resource "azurerm_dns_zone" "zone" {
      name = (
        var.dns_zone_name != null ?
        var.dns_zone_name :
        "www.${random_string.azurerm_dns_zone_name.result}.azurequickstart.org"
      )
      resource_group_name = azurerm_resource_group.rg.name
    }
    
    resource "azurerm_dns_a_record" "record" {
      name                = "www"
      resource_group_name = azurerm_resource_group.rg.name
      zone_name           = azurerm_dns_zone.zone.name
      ttl                 = var.dns_ttl
      records             = var.dns_records
    }
    
  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."
    }
    
    variable "dns_zone_name" {
      type        = string
      default     = null
      description = "Name of the DNS zone."
    }
    
    variable "dns_ttl" {
      type        = number
      default     = 3600
      description = "Time To Live (TTL) of the DNS record (in seconds)."
    }
    
    variable "dns_records" {
      type        = list(string)
      default     = ["1.2.3.4", "1.2.3.5"]
      description = "List of IPv4 addresses."
    }
    
  5. Create a file named outputs.tf and insert the following code:

    output "resource_group_name" {
      value = azurerm_resource_group.rg.name
    }
    
    output "dns_zone_name" {
      value = azurerm_dns_zone.zone.name
    }
    
    output "name_servers" {
      value = azurerm_dns_zone.zone.name_servers
    }
    

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 DNS zone name.

    dns_zone_name=$(terraform output -raw dns_zone_name)
    
  3. Run az network dns zone show to display information about the new DNS zone.

    az network dns zone show \
        --resource-group $resource_group_name \
        --name $dns_zone_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