Course Introduction

Hello and welcome to the Terraform for Beginners lesson! My name is Vijin Palazhi, and I'll be guiding you through this comprehensive introduction to Terraform and Infrastructure as Code (IaC).

In this lesson, you will learn how Terraform fits into modern IT infrastructure management and gain hands-on experience with the HashiCorp Configuration Language (HCL). We start with an overview of Terraform, its role in automating infrastructure, and a discussion on IaC, followed by the installation process. Once installed, you'll dive into HCL basics to set the foundation for subsequent practical labs.

After establishing the fundamentals, we will explore core Terraform concepts including:

• Providers and Resources: Understand how Terraform interacts with various cloud and on-premises services.
• Input and Output Variables: Learn to parameterize configurations.
• Dependencies and Resource Attributes: Discover how resource relationships are managed.
• Terraform State: Dive into what state is, its significance, and best practices for state management.

Next, we will cover an in-depth exploration of Terraform commands along with a detailed discussion on mutable versus immutable infrastructure, which shapes how your resources are managed over time.

The lesson then transitions to vital topics including:

• Data Sources & Meta-Arguments: Explore how to integrate existing resources into Terraform configurations, using arguments like count and for_each.
• Version Constraints: Learn how to control provider and module versions.
• AWS Essentials: An optional lecture segment will walk you through setting up an AWS account and configuring core services like IAM, S3, and DynamoDB—with practical labs demonstrating how to provision and manage these services via Terraform.

In addition to the above topics, advanced concepts such as remote state management, state locking, and using an S3 backend to store your state file will be taught. You'll also see how Terraform state commands are used to maintain and troubleshoot state files.

Following the discussion on state management, the course introduces AWS EC2 through live demonstrations on provisioning instances using Terraform.

We also cover additional advanced functionalities:

• Provisioners: Explanation of what provisioners are, the different types, and best practices.
• Resource Taints and Debugging: How to mark resources for re-creation, enable debugging, and import external resources into Terraform management.
• Terraform Modules: Learn how to create and reuse modules and leverage pre-built modules from the Public Terraform Registry.

We'll wrap up the core content by discussing Terraform functions, conditional expressions (including testing them in the Terraform console), and workspaces—what they are, how to create them, and when they are useful. Finally, a high-level overview of the features offered by Terraform Cloud is provided.

Below is an example configuration illustrating the deployment of an AWS instance with associated resources:

resource "aws_instance" "webserver" {
  ami           = "ami-1a2b3c4d5e6f7g8h9"
  instance_type = "t2.micro"

  user_data = <<-EOF
              #!/bin/bash
              sudo apt update
              sudo apt install nginx -y
              systemctl start nginx
              EOF

  key_name              = aws_key_pair.web-id
  vpc_security_group_id = aws_security_group.ssh-access.id
}

resource "aws_security_group" "ssh-access" {
  ...
}

$ terraform destroy

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

...

resource "local_file" "pet" {
  filename = "/root/pets.txt"
  content  = "We love pets!"
}

In the AWS section, demonstration videos will guide you through getting started with AWS services via the AWS Management Console. These demonstrations include setting up essential services such as IAM, DynamoDB, and EC2 through Terraform, followed by hands-on labs where you provision and manage infrastructure seamlessly.

Below is an example configuration for setting up the AWS provider:

provider "aws" {
  region = "ca-central-1"
}

After configuring the provider, you might validate your Terraform configuration using the following command:

iac-server $ terraform validate
Error: Missing required argument

  The argument "region" is required, but was not set.

iac-server $ terraform validate

I am very excited to begin this journey with you. Let's get started!