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Terraform Automation Best Practices

Learn Terraform automation best practices for managing infrastructure efficiently and securely. Explore core principles, version control, security, state management, CI/CD integration, testing, and advanced techniques.

Zan Faruqui
May 16, 2023

Terraform automation simplifies managing your infrastructure by turning it into code, enabling you to set up, manage, and modify your tech environment efficiently and reliably. This guide dives into best practices for Terraform automation, covering everything from setting up your environment to scaling your automation efforts. Here's a quick overview of what we'll cover:

  • Setting Up Your Terraform Environment: Learn the initial steps to get started, including installing Terraform CLI and configuring cloud provider credentials.
  • Terraform Automation Core Principles: Understand the key principles for effective Terraform automation, such as the Infrastructure as Code mindset and standardized module structure.
  • Version Control and Collaboration: Discover how to manage your Terraform code with Git for better teamwork and code quality.
  • Terraform Configuration Best Practices: Tips on structuring your Terraform code for clarity and maintainability.
  • Security and Compliance: Guidelines for keeping your Terraform automation secure and compliant with industry standards.
  • Terraform State Management: Strategies for managing Terraform's state, ensuring consistency and collaboration.
  • Automating Terraform Workflows: How to integrate Terraform into CI/CD pipelines for seamless automation.
  • Advanced Terraform Automation Techniques: Explore methods for managing large-scale infrastructure and multi-environment deployments.
  • Testing and Validation: Learn about tools and practices for testing and validating your Terraform configurations.

By following these best practices, you'll be able to leverage Terraform automation effectively, making your infrastructure management more streamlined, secure, and scalable.

What is Terraform?

Created by HashiCorp, Terraform is a free tool that helps you describe your tech infrastructure in a straightforward way. You can tell it exactly how you want things set up for services like AWS, Azure, Google Cloud, and more. Here's why it's handy:

  • Infrastructure as Code: You write down your setup plans, making it easy to keep track and work together on them.
  • Execution Plans: Terraform shows you what it will do before it does anything, helping you avoid surprises.
  • Resource Graph: It helps you see how different parts of your setup depend on each other.
  • Change Automation: With Terraform, making big changes doesn't need much manual work.
  • Multi-Provider: It works with many different cloud services and tech setups.

Terraform's Role in DevOps

Terraform fits right into the DevOps way of doing things, which is all about making software and updates smoothly and continuously:

  • Provisioning: It can set up infrastructure automatically when needed.
  • Changing: You can update your setup just by tweaking the code and running Terraform again.
  • Versioning: Since your setup is written as code, you can keep versions of it, just like you do with software code.
  • Destroying: It's easy to take down stuff you don't need anymore.

Using Terraform means you're keeping up with modern practices like version control and automation.

Terraform Components

Here are the main parts of Terraform you should know about:

  • Providers: These are like bridges that let Terraform talk to and manage different cloud platforms and services.
  • Modules: Think of these as building blocks for your setup that you can use over and over.
  • Workspaces: These are separate areas where you can manage different versions or parts of your infrastructure without mixing them up.
  • State: This is a special file that keeps track of everything Terraform is managing, making sure the plan matches what's really happening.

Setting Up Your Terraform Environment

Getting started with Terraform means setting up your space to work smoothly. Here are the steps to get everything ready:

Install Terraform CLI

The Terraform CLI is your main tool for running Terraform commands. Check that you have the newest version on your computer or CI/CD server. You can find how to install it based on your computer's operating system in the Terraform installation guides.

Configure Cloud Provider Credentials

Terraform needs to know how to talk to your cloud services like AWS, Azure, or GCP. You'll need to set up access with credentials, either in a file or as environment variables. Look at the Terraform provider guides for how to do this.

Set Up a Remote State Backend

Instead of keeping your Terraform state file on your computer, put it somewhere online like S3 or GCS. This lets your team access it and keeps it safe if things change. Here's an example of how to set it up for S3:

terraform {
  backend "s3" {
    bucket = "mybucket"
    key    = "path/to/my/key"
    region = "us-east-1" 

Create a Terraform Module Structure

Break up your Terraform code into modules for different parts like networking, computing, and databases. This makes it easier to handle and work on as a team.


Use a Private Module Registry

Module Registry

Keep your private Terraform modules in a place where your team can easily find and use them. You can use Terraform Cloud, AWS S3, or set up your own with Terraform Enterprise.

Configure CI/CD Integration

Make sure Terraform works with your CI/CD setup for automatic testing and deployment. You can use tools like GitHub Actions, CircleCI, TravisCI, or Jenkins to do this.

By following these steps, you create a good foundation for working with Terraform. This setup helps you and your team manage your infrastructure code better.

Terraform Automation Core Principles

When you use Terraform to automate setting up your infrastructure, there are a few key ideas and best practices to keep in mind to make everything work smoothly, reliably, and in a way that everyone can get on board with.

The Infrastructure as Code Mindset

Thinking of your infrastructure like it's code changes how you handle your resources. Just like with app code, you should:

  • Keep all your Terraform files in version control
  • Have a clear process for testing and moving changes along
  • Write down explanations for your components so others get how they work

This approach lets you make changes fast but safely.

Standardized Module Structure

It's crucial to organize your Terraform setup into modules that you can use again and again. Here are some tips:

  • Make separate modules for different parts (like networking, servers, databases)
  • Make sure modules only show the inputs and outputs that are needed
  • Stick to a clear naming system and file setup so people can find what they need
  • Keep your own modules in a private registry

Doing this makes it much easier for everyone to work together.

Automated Testing and Deployment

Treat your Terraform code like you would your app code by:

  • Creating tests to check your changes and find any issues
  • Running automatic checks to make sure everything meets the rules
  • Setting up automatic processes to put changes in place
  • Using workspaces to handle different environments

This helps you move faster while cutting down on mistakes.

Remote State Management

Instead of keeping your Terraform state file on your computer, use a remote backend:

  • This lets your team work together better
  • Keeps your state safe outside your local setup
  • Stops more than one person from making changes at the same time
  • Lets you keep track of your state over time, just like other files

Remote state is key to making Terraform work well for more people and projects.

Following these ideas helps you set up Terraform automation in a way that's efficient, safe, and team-friendly. It's all about treating your infrastructure as if it's code and enjoying the benefits of that approach.

Version Control and Collaboration

Keeping track of your Terraform code and working together as a team is super important. Here's how to do it right:

Use Git for Version Control

  • Put all your Terraform files in a Git repository. This helps you keep track of changes and go back if needed.
  • Make small changes and describe what you did when you save them.
  • Before adding changes to the main project, have someone else look them over.
  • Use Git tags to mark versions that are ready for real use.
  • Keep a clean setup with a main branch for the final version and a development branch for testing new stuff.

Using Git makes it easier for everyone to see what's changed and helps keep things from getting mixed up.

Structure Code for Modularity

  • Organize your code into modules, like pieces for networking or services, that you can use again.
  • Make sure each module only shows what's needed to use it.
  • Stick to a clear way of naming things and setting up your project.
  • Put instructions or guides (README docs) in your modules to help others understand them.

This setup makes it simpler to work on projects together, test things out, and use pieces of code in different places.

Use Private Module Registry

  • Keep your own modules in places like Terraform Cloud or AWS S3.
  • Set who can see or use your modules.
  • Make sure modules are checked by others before they're shared.
  • Use SemVer (a way of naming versions) to keep things organized.

Having a central place for your modules makes it easier to find and manage them. It also means you can make sure everything meets your standards before others use it.

Segregate Environments with Workspaces


  • Use different workspaces for different parts of your project, like development, testing, and production.
  • Change settings with variables to fit each environment.
  • Pick a place to keep your Terraform state that's separate for each workspace.

Workspaces help you manage changes safely and keep your project organized, making sure that updates go smoothly from one stage to the next without any mix-ups.

Terraform Configuration Best Practices

Follow a Standard Module Structure

Standard Module Structure

It's a good idea to organize your Terraform setup in a tidy way. Here's how you can do it:

  • Keep all your modules in a modules/ folder at the top level of your Terraform setup
  • Sort these modules into folders based on what they do (like networking, compute, database)
  • Each module should have a file that lists what it's supposed to do
  • Keep anything specific to that module, like variables or outputs, inside its folder

This method makes it easier to find and update your modules, and you can use them again in different projects.

Adopt a Naming Convention

Using clear and consistent names helps everyone understand your Terraform code better. Here are some tips:

  • Use lower_snake_case for naming resources (like aws_instance.web_server)
  • Start resource names with their type (like aws_vpc, google_storage_bucket)
  • For input variables, use lower_snake_case and start with var_ (like var_instance_type)
  • For outputs, use lower_snake_case and start with output_ (like output_lb_dns_name)

Sticking to a naming rule helps avoid mix-ups and makes your code easier to read.

Use Variables and Outputs Judiciously

Being smart about how you use input variables and outputs can make your modules more useful and easier to work with:

  • Use input variables for things that might change when you use the module
  • Set defaults for resources that fit what you usually need
  • If necessary, let users tweak more specific properties with extra variables
  • Make sure to hide sensitive info in variables so it doesn't show up in logs
  • Only share outputs from child modules that are needed by the main setup
  • Name your outputs in a way that clearly says what they are

By doing this, you make your modules flexible and keep them simple, which helps when connecting different parts of your Terraform code.

Security and Compliance in Terraform Automation

When you're setting up your systems with Terraform, it's really important to keep things safe and follow the rules. Here's how to do that in simple steps:

Store Sensitive Data Securely

  • It's a good idea to keep things like passwords and API keys in a safe place. Services like HashiCorp Vault or AWS Secrets Manager are great for this.
  • In your Terraform code, use a data source to grab these secrets when needed, instead of putting them directly in your code.
  • Make sure any place you're keeping your Terraform files online (like S3) is set to keep your data safe (encrypted).

Limit Access and Permissions

  • Only give Terraform the minimum access it needs to do its job. This helps prevent accidents.
  • If you're using Terraform in automated setups, like CI/CD pipelines, use temporary access keys.
  • Turn on extra protections (like MFA delete) on your remote state files in S3.

Validate Code Security

  • Always run terraform validate to catch any mistakes.
  • Use tools like Checkov or Tfsec to check your Terraform files for security issues before you apply them.
  • Try a test run (dry run) of your Terraform plan to make sure it does what you expect without any surprises.

Backup Critical Data

  • Keep versions of your remote state files to go back to earlier versions if needed.
  • Regularly back up these state files and any other important info.

Monitor Infrastructure Changes

  • Set up alerts for when your Terraform setup changes things.
  • Use tools that check your Terraform plans to make sure they fit with your policies.
  • Keep an eye on your setup even after Terraform has done its job to catch any unexpected changes.

By focusing on these security and rule-following steps, you can use Terraform safely to set up your cloud stuff without worrying about making mistakes or breaking important rules.

Terraform State Management

Terraform State

Managing how Terraform keeps track of your setup is super important for making sure everything runs smoothly. Here are some smart moves to make:

Use Remote State

  • It's best to keep the record of your Terraform setup (called state) in a place like S3 or GCS, not just on your computer
  • This lets your whole team work on it together
  • Helps avoid messing up the state file, which can happen if it's just stored locally
  • You can also keep track of changes over time this way

Example S3 Backend Configuration

terraform {
  backend "s3" {
    bucket = "my-terraform-state"
    key    = "env/dev/terraform.tfstate"
    region = "us-east-1"

Implement State Locking

State Locking

  • Terraform needs to make sure no two people try to change things at the same time
  • Locking the state stops more than one update happening at once, which could mess things up
  • You can use something like DynamoDB or Consul to keep the state locked when needed

Example Using DynamoDB

terraform {
  backend "s3" {
    bucket         = "my-terraform-state"
    key            = "env/dev/terraform.tfstate"
    region         = "us-east-1"
    dynamodb_table = "terraform-state-locks"

Regularly Back Up State Files

  • Make sure to save copies of your remote state files to a safe place like S3
  • This means you can go back to an earlier setup if you need to
  • Use tools from your cloud service to set up automatic backups

Example AWS Backup Rule

resource "aws_backup_plan" "tfstate_backup" {
  name = "tfstate_backup"

  rule {
    rule_name         = "tfstate_daily"
    target_vault_name =
    schedule          = "cron(0 5 * * ? *)"

    lifecycle {
      cold_storage_after = 0
      delete_after       = 90

By sticking to these tips for managing the state, you'll help keep your Terraform projects running without a hitch and safe.


Automating Terraform Workflows

Implementing CI/CD Pipelines

Integrating Terraform with your CI/CD setup helps automate setting up your tech stuff by running terraform plan and terraform apply as part of your pipeline. This way, changes to your infrastructure go through the same checks and tests as your app changes.

How to do it:

  • Add steps in your CI/CD jobs for setting up and running Terraform.
  • Start with terraform init to get everything ready.
  • Use terraform plan to see what changes will happen.
  • You might want to check your plan for any issues with terraform validate or by looking at the plan's output.
  • Use tools like Terratest or Kitchen-Terraform to test if your infrastructure builds correctly.
  • If everything looks good, either automatically or after someone approves it, run terraform apply.
  • For really important setups, like production, think about using Terraform Cloud for running these commands safely off your CI/CD server.

Following these steps makes sure Terraform runs smoothly within your existing workflow, while still keeping things safe and checked.

Using Terraform Cloud for Automation

Terraform Cloud

Terraform Cloud offers a bunch of tools to help with Terraform automation, including:

  • Running terraform plan and terraform apply safely away from your main setup.
  • Keeping your Terraform state file safe with backups and versioning.
  • Connecting to your code repository to start runs when code changes.
  • Showing what changes would look like without actually applying them.
  • Checking your Terraform files against rules you set.
  • Letting you control who can approve big changes.
  • Sending updates to your team about what's happening.

To use it:

  • Add a cloud block in your Terraform files to use Terraform Cloud.
  • Connect your code repository to start automation when you push changes.
  • Set up any rules for checking your Terraform files.
  • Decide how changes get approved with run triggers and policy checks.
  • Watch and manage runs in the Terraform Cloud website, and set up notifications to keep everyone in the loop.

Terraform Cloud takes care of the heavy lifting and offers useful tools while letting you keep control over what gets applied and when.

Controlling Terraform Output in Automation

When using Terraform automatically, it's important to manage the messages it shows to keep your logs tidy and safe.

Here are some tips:

  • Use TF_IN_AUTOMATION=true to keep the output simple.
  • Add -input=false to stop Terraform from asking for input.
  • Manage where messages go with your CI/CD tools, or turn them off if needed.
  • Use TF_CLI_ARGS="-no-color" to get rid of colors in the output.
  • Turn on detailed exit codes to catch warnings with terraform apply.

For older versions of Terraform, you might also need:

  • TF_LOG=TRACE for troubleshooting.
  • TF_LOG_PATH=./terraform.log to save log messages to a file.

Keeping your Terraform output under control helps make sure your automation runs smoothly and keeps your info safe.

Advanced Terraform Automation Techniques

Multi-Environment Deployment Strategies

When you're managing different stages of your project, like development, testing, and production, it's smart to use separate spaces for each. This keeps things organized. You can set up a unique storage spot for each environment using a backend configuration like this:

terraform {
  backend "s3" {
    bucket = "dev-terraform-state"

terraform {
  backend "s3" {
    bucket = "test-terraform-state"  

terraform {
  backend "s3" {
    bucket = "prod-terraform-state"

Then, you create a workspace for each environment and deploy your resources there:

terraform workspace new dev
terraform apply

terraform workspace new test
terraform apply

terraform workspace new prod 
terraform apply

Leverage Pre-installed Plugins

You can make Terraform work faster by setting up plugins ahead of time in a common folder. This way, Terraform won't have to download them every time you run it. You can tell Terraform where to find these plugins with the -plugin-dir flag:

mkdir /opt/terraform/plugins
terraform init -plugin-dir=/opt/terraform/plugins

This is a neat trick to speed things up, especially when you're working in a team.

Optimizing for Large-Scale Infrastructure

If you're dealing with a big setup, Terraform Cloud Agents can help by spreading out the work across several machines. Here are some more tips for managing large projects:

  • Break your setup into smaller pieces, each with its own state file. This could be by region or another logical division.
  • Use tools like Ansible, Salt, or Chef to manage resources across many machines.
  • Speed things up by creating resources all at once with the for_each command.

These tips can help you manage big projects more smoothly and quickly.

Testing and Validation

Terraform Built-in Validation

Terraform comes with tools to help make sure your setup is correct before you actually start using it:

  • terraform validate looks for mistakes in your code and checks if everything is set up right, without making any changes. It's a good idea to use this often while you're working.
  • terraform plan shows what will happen when you make changes. It's important to look at this closely to catch anything unexpected.
  • terraform fmt helps tidy up your code by formatting it the right way. Do this before you save your code.

These tools are great for quick checks during your work to find and fix problems early.

Third-party Testing Tools

You can also use extra tools with Terraform to make sure everything works well:

  • Linters like tflint help find errors, outdated code, or things you don't need anymore.
  • Security scanners like Checkov look for settings that might make your setup less secure.
  • Testing frameworks like Terratest and Kitchen-Terraform actually set up resources to test if your infrastructure code works.


  • Start with quick and simple checks, like terraform validate, to catch easy fixes first.
  • Test one piece at a time before trying everything together.
  • Use a different testing area so you don't mess up your main setup.
  • Make sure to remove any test setups when you're done.

Following these steps helps make your code better and keeps problems away from your live setup.

Scaling Terraform Automation

As your projects and team get bigger, it's key to keep your Terraform setup running smoothly and easy to handle. Here are some smart tips for doing just that:

Modular Architecture

  • Split your Terraform setup into smaller parts, like modules for networking, computers, storage, etc.
  • Make sure each module only shows what you need to see and use.
  • Use modules that have been tested and approved across different setups.
  • Keep your modules in a place like the Terraform Cloud where your team can easily find and use them.

Remote State Management

  • Store your Terraform information online with remote state to let more than one person work on it at the same time without problems.
  • Use state locking to stop people from making changes at the same time.
  • Make sure you have backup plans and control who can access the remote state.

Automated Testing

  • Add testing tools like Terratest and Kitchen-Terraform to your CI/CD pipelines.
  • Test your modules on their own before putting them all together.
  • Create tests that check if everything works right, is safe, and follows rules.

Policy Enforcement

  • Use Sentinel policies to make sure everyone follows the rules and limits.
  • Make sure policy checks are part of the process with tools like Terraform Cloud.
  • Use security tools like Checkov to look over your setups.

Delegated Permissions

  • Keep passwords and keys safe with tools like Vault or AWS Secrets Manager.
  • Give people only the access they need to do their job.
  • Use group roles and permissions to keep risks low.

Optimized Execution

  • Make resources at the same time using Terraform's for_each option.
  • Spread out work with Terraform Cloud agents.
  • Keep your Terraform information in different places based on the region or other ways of splitting it up.

By sticking to these tips, you can make sure your Terraform can handle bigger projects while keeping everything safe, following rules, and moving fast.


Making your Terraform setup work well is all about using smart practices from the start. Here's a quick rundown of what we've talked about to help you create a setup that's easy to manage, safe, and works well as your needs grow.

Structure and Style

  • Keep your files organized and use names that make sense.
  • Break your code into smaller parts that you can use again.
  • Regularly check your code to catch mistakes and keep it tidy.

State Management

  • Keep your Terraform info in a Cloud Storage bucket instead of just on your computer.
  • Make sure only one person can make changes at a time with state locking.
  • Always have backups of your Terraform state.

Testing and Validation

  • Use tools like Terratest and Kitchen-Terraform to make sure everything works.
  • Look for security risks.
  • Make sure your plans fit the rules you've set.


  • Use version control for your Terraform files.
  • Share your reusable parts through a module registry.
  • Use Terraform workspaces to keep different project parts separate.


  • Keep login info and other secrets safe.
  • Check who has access to what.
  • Make sure to encrypt any sensitive data.


  • Use CI/CD pipelines to make changes smoothly.
  • Keep your Terraform messages clear and to the point.
  • Take advantage of Terraform Cloud for more control.


  • Use a modular architecture to keep things organized.
  • Manage your Terraform state in the cloud.
  • Automate testing to catch issues early.
  • Use policies to make sure everyone follows the rules.
  • Make sure permissions are set up right.

Getting these basics down will help you manage your infrastructure better as it grows. The effort you put in now will save you a lot of time and trouble later.

We're here to help if you need it, especially when it comes to setting up a Terraform environment that's secure and can grow with you.

How is Terraform used for automation?

Terraform makes it easier to set up and change your tech stuff by following these steps:

  • Get everything ready to go
  • Figure out what needs to change to get your setup just right
  • Check the plan to make sure it looks good
  • Make those changes to build or update things

You can automate this process, like making it part of a CI/CD pipeline, so your tech setup updates whenever you change your application code.

What are the best practices for Terraform?

Here are some smart ways to use Terraform:

  • Keep your code organized with a standard module structure
  • Use clear names so everyone knows what's what
  • Be smart about using variables for flexibility
  • Only show the outputs you really need from modules
  • Use data sources to avoid repeating yourself
  • Try not to rely too much on custom scripts or things outside Terraform
  • Keep helper scripts and static files in their own spots

What are the 4 steps in Terraform GitOps?

To use GitOps with Terraform, do this:

  • Create a Git repo for your Terraform code
  • Write your code to describe how you want your tech setup to look
  • Set up a process that automatically checks and applies your code changes
  • Use pull requests for checking and okaying changes

This way, your infrastructure changes are part of your regular Git workflow.

What is the weakness of Terraform?

Terraform can get tricky when you're dealing with a lot of stuff, like:

  • Using workspaces to handle different settings
  • Keeping track of your code versions
  • Setting up remote backends for storing your Terraform state
  • Understanding how all your resources are connected and managed

As your setup grows, your Terraform code can become harder to manage and more likely to have mistakes. Planning and keeping things tidy is key.

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