Terraform Best Practices and Guidelines

Use HashiCorp Terraform effectively

Terraform Best Practices and Guidelines are a set of recommended principles and strategies that help organizations use HashiCorp Terraform effectively and efficiently to manage infrastructure as code (IaC).

These practices aim to promote consistency, reliability, security, and scalability in the process of provisioning and managing cloud resources and are based on Awarala's real world experience running critical production cloud SaaS.

Here are some Terraform best practices and guidelines to consider:

Modularization and Reusability

• Organize your Terraform code into modular components (modules) that encapsulate specific functionality.
• Promote code reuse by designing modules that can be easily shared across projects and environments.

Version Control

• Use a version control system (e.g., Git) to track changes to your Terraform codebase.
• Follow Git best practices, such as branching, tagging, and committing meaningful messages.

Infrastructure as Code (IaC) Principles

• Treat infrastructure code like software code, applying coding practices such as code reviews, linting, and automated testing.
• Embrace the "single source of truth" principle by managing all infrastructure changes through Terraform code.

State Management

• Store Terraform state files in a secure and centralized location, such as a version-controlled repository or a remote state backend.
• Implement state locking to prevent concurrent modifications to the same state file.

Secrets Management

• Avoid hardcoding sensitive information (e.g., passwords, access keys) in your Terraform code.
• Utilize secrets management tools or services to securely store and retrieve sensitive data.

Variable Usage

• Use variables to parameterize your Terraform code, making it more flexible and adaptable to different environments.
• Centralize variable definitions and provide meaningful default values.

Code Formatting and Style

• Adhere to consistent code formatting and style guidelines to improve readability and maintainability.
• Utilize tools like Terraform's built-in formatter ("terraform fmt") to automatically format code.

Documentation

• Document your Terraform code, modules, and configurations to provide context and usage instructions for team members.
• Include comments and annotations to explain complex logic, design decisions, and business requirements.

Automated Testing

• Implement automated testing for your Terraform code to catch errors and ensure correct behavior.
• Use testing frameworks like Terratest or Kitchen-Terraform to validate your infrastructure deployments.

Infrastructure Review Process

• Establish a review process for infrastructure changes, involving code reviews, testing, and validation.
• Use peer reviews to ensure that code follows best practices and aligns with organizational standards.

Stateless Resource Creation

• Design your Terraform code to be idempotent, meaning that it can be safely applied multiple times without causing unintended changes.
• Avoid relying on external data sources for resource creation, as they can introduce non-deterministic behavior.

Monitoring and Observability

• Implement monitoring and observability tools to track the state and performance of your infrastructure resources.
• Incorporate logging, metrics, and alerts to proactively identify and address issues.

By following these Terraform best practices and guidelines, organizations can build a solid foundation for managing infrastructure as code, streamline collaboration among team members, and ensure that their infrastructure deployments are reliable, secure, and scalable.