Build Infrastructure

In this tutorial, you will create a Terraform configuration to deploy an Azure resource group. This resource group is the foundation for the infrastructure you will build in the subsequent tutorials.

»Prerequisites

• An Azure subscription. If you don't have an Azure account, create one now. This tutorial can be completed using only the services included in an Azure free account.

• Terraform 0.12.6 or later

• The Azure CLI Tool installed

»Install the Azure CLI tool

You will use the Azure CLI tool to authenticate with Azure.

$ Invoke-WebRequest -Uri https://aka.ms/installazurecliwindows -OutFile .\AzureCLI.msi; Start-Process msiexec.exe -Wait -ArgumentList '/I AzureCLI.msi /quiet'; rm .\AzureCLI.msi

»Authenticate using the Azure CLI

Terraform must authenticate to Azure to create infrastructure.

In your terminal, use the Azure CLI tool to setup your account permissions locally.

$ az login

Your browser window will open and you will be prompted to enter your Azure login credentials. After successful authentication, your terminal will display your subscription information. You do not need to save this output as it is saved in your system for Terraform to use.

You have logged in. Now let us find all the subscriptions to which you have access...

[
  {
    "cloudName": "AzureCloud",
    "homeTenantId": "0envbwi39-home-Tenant-Id",
    "id": "35akss-subscription-id",
    "isDefault": true,
    "managedByTenants": [],
    "name": "Subscription-Name",
    "state": "Enabled",
    "tenantId": "0envbwi39-TenantId",
    "user": {
      "name": "your-username@domain.com",
      "type": "user"
    }
  }
]

»Create your initial configuration

$ New-Item -Path "c:\" -Name "learn-terraform-azure" -ItemType "directory"

Create a new file called main.tf and paste the configuration below.

# Configure the Azure provider
terraform {
  required_providers {
    azurerm = {
      source = "hashicorp/azurerm"
      version = ">= 2.26"
    }
  }
}

provider "azurerm" {
  features {}
}

resource "azurerm_resource_group" "rg" {
  name     = "myTFResourceGroup"
  location = "westus2"
}

The format for resource identifier in Terraform configuration is <_type_>.<_name_>. In the sample configuration above, the resource ID is azurerm_resource_group.rg.

This configuration provisions an azurerm_resource_group resource named rg. The resource name is used to reference the Terraform resource created in the resource block throughout the configuration. It is not the same as the name of the resource group in Azure.

»Initialize your Terraform configuration

Initialize your learn-terraform-azure directory in your terminal. The terraform commands will work with any operating system.

$ terraform init

Your output should look similar to the one below.

Initializing the backend...

Initializing provider plugins...
- Checking for available provider plugins...
- Downloading plugin for provider "azurerm" (terraform-providers/azurerm) v2.26.0...

Terraform has been successfully initialized!

»Plan your Terraform Run

Before you can create infrastructure, Terraform needs to generate an execution plan.

Run the terraform plan command to view the execution plan for your configuration.

$ terraform plan

The execution plan specifies what actions Terraform will take to achieve the desired state defined in the configuration. Your execution plan should look similar to the output below.

An execution plan has been generated and is shown below.
Resource actions are indicated with the following symbols:
  + create

Terraform will perform the following actions:

  # azurerm_resource_group.rg will be created
  + resource "azurerm_resource_group" "rg" {
      + id       = (known after apply)
      + location = "westus2"
      + name     = "myTFResourceGroup"
      + tags     = (known after apply)
    }

Plan: 1 to add, 0 to change, 0 to destroy.

»Apply your Terraform Configuration

Run the terraform apply command to apply your configuration.

$ terraform apply

This output shows the execution plan and will prompt you for approval before proceeding. If anything in the plan seems incorrect or dangerous, it is safe to abort here with no changes made to your infrastructure. Type yes at the confirmation prompt to proceed.

After confirming your execution plan, Terraform will create your resource group.

Plan: 1 to add, 0 to change, 0 to destroy.

Do you want to perform these actions?
  Terraform will perform the actions described above.
  Only 'yes' will be accepted to approve.

  Enter a value: yes

azurerm_resource_group.rg: Creating...
azurerm_resource_group.rg: Creation complete after 1s [id=/subscriptions/159f2485-xxxx-xxxx-xxxx-xxxxxxxxxxx/resourceGroups/myTFResourceGroup]

Apply complete! Resources: 1 added, 0 changed, 0 destroyed.

Navigate to the Azure portal in your web browser to validate the resource group.

»Inspect your state

When you apply your configuration, Terraform writes data into a file called terraform.tfstate. This file contains the IDs and properties of the resources Terraform created so that it can manage or destroy those resources going forward. Your state file contains all of the data in your configuration and could also contain sensitive values in plaintext, so do not share it or check it in to source control.

For teams or larger projects, consider storing your state remotely. Remote stage storage enables collaboration using Terraform but is beyond the scope of this tutorial.

Inspect the current state using terraform show.

$ terraform show
# azurerm_resource_group.rg:
resource "azurerm_resource_group" "rg" {
    id       = "/subscriptions/subscription-id/resourceGroups/myTFResourceGroup"
    location = "westus2"
    name     = "myTFResourceGroup"
}

When Terraform created this resource group, it also gathered the resource's properties and meta-data. These values can be referenced to configure other resources or outputs, which you will encounter in later tutorials.

To review the information in your state file, use the state command. If you have a long state file, you can see a list of the resources you created with Terraform by using the list subcommand.

$ terraform state list
azurerm_resource_group.rg

If you run terraform state, you will see a full list of available commands to view and manipulate the configuration's state.

$ terraform state
Usage: terraform state <subcommand> [options] [args]

  This command has subcommands for advanced state management.

  These subcommands can be used to slice and dice the Terraform state.
  This is sometimes necessary in advanced cases. For your safety, all
  state management commands that modify the state create a timestamped
  backup of the state prior to making modifications.

  The structure and output of the commands is specifically tailored to work
  well with the common Unix utilities such as grep, awk, etc. We recommend
  using those tools to perform more advanced state tasks.

Subcommands:
    list                List resources in the state
    mv                  Move an item in the state
    pull                Pull current state and output to stdout
    push                Update remote state from a local state file
    replace-provider    Replace provider in the state
    rm                  Remove instances from the state
    show                Show a resource in the state

»Next Steps

For more detail on the concepts we used in this tutorial:

• Read about the format of the configuration files in the terraform documentation.
• Learn more about Terraform providers.
• Review usage examples of the Terraform Azure provider from Terraform provider engineers