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Free Terraform Training

If you'd prefer to learn a few of the basics via YouTube, check out the following link:

Terraform Basics

What Is Terraform?

Terraform is an open-source infrastructure as code software tool created by HashiCorp. Users define and provide data center infrastructure using a declarative configuration language known as HashiCorp Configuration Language (HCL), or optionally

What Is HCL?

This low-level syntax of the Terraform language is defined in terms of a syntax called HCL, which is also used by configuration languages in other applications, and in particular other HashiCorp products. HCL was created to be human-readable and easier to work with instead of using JSON or YAML. HCL is a functional-based programming language

Terraform Developer Concepts

  • Immutable: Cannot be changed after a resource is created. Instead, it gets replaced/re-created.
  • Mutable: Can be changed after a resource is created

Terraform Terminology

Programmatic Terminology

  • Provider: Providers interact with sources (AWS, Azure, Cloudflare, etc.) at the programmatic level via API calls.
  • Module: A folder that contains all of the Terraform resources that you're utilizing. For example, if you have a directory called s3-bucket and inside of it is a Terraform resource to create an S3 bucket, that would be a Module
  • State: The tfstate is cached metadata about the configurations that are created/replaced/updated/delete in a Terraform module.
  • Data Source: Return information on resources. For example, to return the metadata of an S3 bucket.
  • Output Values: Values returned after creating resources via Terraform that can be used for other configurations or just as information.
  • Backend: Defines where and how operations are performed, where state snapshots are stored, etc.
  • Remote State: Store the state in a remote location (S3 bucket for example).

Creating/Replacing/Updating/Deleted Terraform Resources

  • Init: Initialize a Terraform module to be ready to create/replace/update/delete resources. init also downloads the Provider and stores it in the Terraform module.
  • Plan: Determines what needs to be created/replaced/updated/deleted to move to the desired state.
  • Apply: Creates/replaces/updates/deletes the resources via Terraform
  • Destroy: Deletes the resources in the Terraform module
  • Resources: A block of code to create/replace/update/delete services, servers, etc.. For example, an S3 bucket.