Terraform is a fantastic tool for managing infrastructure, but without good practices, things can get messy—fast. Imagine a world where:
- Terraform state files vanish into thin air.
- Untracked changes wreck your deployments.
- Infrastructure drifts into an unknown state.
Sounds like a nightmare, right?
In this post, we’ll cover Terraform best practices that will keep your infrastructure secure, scalable, and maintainable—without turning into a DevOps horror story.
Let’s get started!
1. Use Remote State to Prevent Disaster
Terraform’s state file (terraform.tfstate) is the single source of truth for your infrastructure. Losing or corrupting it is like losing the map to your treasure—and that treasure is your entire cloud environment!
Bad Idea: Storing State Locally (Don’t Do This!)
By default, Terraform stores state on your local machine, which means:
- If your laptop dies, so does your state file.
- You can’t collaborate with a team.
- Risk of accidentally deleting infrastructure.
Best Practice: Use a Remote State Backend
Store your Terraform state in a remote backend like Azure Blob Storage, AWS S3, or Terraform Cloud to:
- Enable team collaboration.
- Keep state files secure and backed up.
- Prevent accidental loss of infrastructure data.
Example: Storing State in Azure Blob Storage
terraform {
backend "azurerm" {
resource_group_name = "myResourceGroup"
storage_account_name = "mystorageaccount"
container_name = "tfstate"
key = "terraform.tfstate"
}
}
Bonus: Use state locking to prevent multiple people from modifying Terraform at the same time.
2. Keep Your Terraform Code DRY (Don’t Repeat Yourself)
Copy-pasting Terraform code across multiple projects or environments is a disaster waiting to happen. Instead, make your code modular and reusable.
Best Practice: Use Modules
Terraform modules let you define reusable infrastructure components that can be called from different projects.
Example: A Module for Deploying an Azure Resource Group
Create a module folder:
mkdir -p modules/resource_group
Inside modules/resource_group/main.tf:
resource "azurerm_resource_group" "rg" {
name = var.resource_group_name
location = var.location
}
Now, call the module in your Terraform config:
module "my_resource_group" {
source = "./modules/resource_group"
resource_group_name = "TerraformRG"
location = "East US"
}
Result: Clean, reusable, and maintainable Terraform configurations!
3. Use Variables and Outputs for Flexibility
Hardcoding values in Terraform is a recipe for chaos. Instead, use variables and outputs to make your configurations dynamic.
Example: Using Variables for Environment-Specific Configs
variable "environment" {
description = "Deployment environment"
default = "dev"
}
variable "vm_size" {
type = map(string)
default = {
dev = "Standard_DS1_v2"
prod = "Standard_DS3_v2"
}
}
resource "azurerm_virtual_machine" "example" {
name = "myVM"
vm_size = var.vm_size[var.environment]
}
Now, switching environments is as easy as changing one variable!
4. Use Workspaces for Multi-Environment Deployments
Instead of maintaining separate Terraform configs for dev, staging, and prod, use Terraform workspaces to manage them dynamically.
Best Practice: Workspaces for Dev, Staging, and Prod
terraform workspace new dev terraform apply terraform workspace new prod terraform apply
Benefit: One codebase, multiple environments, no duplication!
5. Implement Terraform CI/CD Pipelines
Would you manually run Terraform commands every time you deploy? Heck no! Instead, automate Terraform with CI/CD pipelines like GitHub Actions, Azure DevOps, or GitLab CI/CD.
Example: GitHub Actions Terraform Pipeline
name: Terraform Deployment
on:
push:
branches:
- main
jobs:
terraform:
runs-on: ubuntu-latest
steps:
- name: Checkout Code
uses: actions/checkout@v2
- name: Setup Terraform
uses: hashicorp/setup-terraform@v1
- name: Terraform Init
run: terraform init
- name: Terraform Plan
run: terraform plan
- name: Terraform Apply
run: terraform apply -auto-approve
Benefit: No manual deployments → Terraform runs automatically when code changes!
6. Validate and Format Your Code Before Applying
Before applying Terraform, always validate and format your code to catch errors early.
Run These Checks Before Deployment
1. Format your Terraform code (fixes indentation & styling issues):
terraform fmt
2. Validate your configuration (checks for syntax errors):
terraform validate
3. Preview what Terraform will do before applying:
terraform plan
Why It’s Important: Prevents accidental mistakes before making changes!
7. Secure Secrets: NEVER Hardcode API Keys or Passwords!
Terraform configurations often require sensitive credentials (e.g., database passwords, API keys). Never hardcode these values—use Terraform Vault, AWS Secrets Manager, or Azure Key Vault instead.
Example: Storing Secrets in Azure Key Vault
resource "azurerm_key_vault_secret" "example" {
name = "db-password"
value = "super-secret-password"
key_vault_id = azurerm_key_vault.example.id
}
Benefit: No hardcoded secrets, improved security!
Wrapping Up
Terraform is powerful, but only if used correctly. By following these best practices, you’ll build scalable, secure, and maintainable infrastructure without the headaches.
Quick Recap:
- Use Remote State → Never store state locally!
- Write Reusable Modules → No copy-pasting infrastructure code!
- Use Variables & Outputs → Make configs dynamic!
- Use Workspaces → Manage multiple environments cleanly!
- Automate Terraform with CI/CD → No manual work needed!
- Validate Before Applying → Avoid mistakes!
- Secure Secrets → No hardcoded passwords!
Now, go Terraform smarter, not harder!
What’s Next?
Following best practices is great, but security should always be a top priority in Terraform deployments. In the next post, “Security in Terraform Deployments,” we’ll explore how to protect sensitive data, enforce least privilege access, and secure your infrastructure from misconfigurations—so your cloud stays safe from threats.