Terraform for AWS: Production-Ready Infrastructure as Code

Step 1 – Understand the Terraform on AWS Workflow

• Terraform code describes the desired state (for example “1 VPC + 2 subnets + 1 EC2 instance”).
• Terraform keeps a state file that tracks what is already created in AWS.
• Core commands: terraform init → terraform plan → terraform apply → terraform destroy.

Step 2 – Configure AWS Provider & Credentials

• Install Terraform and configure AWS CLI with an IAM user or role having least-privilege permissions.
• In main.tf add an AWS provider block with region and profile.
• Keep credentials outside the code (profiles, environment variables, SSO) – never hard‑code keys in HCL.

Step 3 – First Resource: EC2 or S3 with Terraform

• Create a simple aws_instance or aws_s3_bucket resource and run terraform apply to see it created in AWS.
• Use tags (Name, Environment, Owner) from day one so resources are easy to track and bill.
• Destroy lab resources with terraform destroy to avoid extra cost.

Step 4 – Variables, Outputs and tfvars

• Move hard‑coded values (region, instance_type, CIDR) into variables.tf and use terraform.tfvars for environment-specific values.
• Use outputs.tf to print important values like instance public IP, ALB DNS name or bucket URL.
• This makes your code reusable for dev, test and prod by just switching tfvars files.

Step 5 – Remote State and Collaboration

• For teams, move state to S3 with state locking in DynamoDB so multiple people do not corrupt the same state.
• Store Terraform code in Git, use branches + PRs, and run terraform plan in CI before applying.
• Treat the state file as sensitive – enable encryption in S3 and restrict access by IAM.

Step 6 – Terraform Modules for AWS VPC & EC2

• Break big configs into modules: for example a vpc module, ec2 module and alb module.
• Use official AWS modules (like terraform-aws-modules/vpc/aws) to follow best practices quickly.
• Wire modules together with inputs/outputs – for example pass VPC ID and subnet IDs from the VPC module into the EC2 and ALB modules.

Step 7 – Mini Project: Terraform AWS Web App Stack

• Create a reusable VPC module with public + private subnets, NAT, route tables and security groups.
• Add an Auto Scaling group of EC2 instances behind an ALB, all created from Terraform.
• Store app assets in S3 and point Route 53 records to the ALB DNS name – entire stack built via terraform apply.
• Use workspaces or separate state files for dev / stage / prod with different CIDRs and sizes.

Next Step – Combine Terraform with AWS DevOps

In real projects, Terraform is usually combined with CI/CD (Jenkins, GitHub Actions or GitLab CI) so infrastructure changes go through the same review process as application code.

If you want to learn this end‑to‑end with mentoring and placement support, check our DevOps Engineering and AWS Cloud courses, where Terraform is used to build complete AWS environments from scratch.