Terraform Agenda

🧭 Key Discussion Points

Terraform Introduction
- What is Terraform?
- Use cases in cloud automation
HashiCorp Configuration Language (HCL)
- Syntax overview
- Declarative structure
Installation & Setup
- Download binary Terraform 1.13.1 Windows Binary
- Verify installation
Benefits & Cons of Terraform
- Pros: modularity, scalability
- Cons: state file complexity
AWS CLI Integration
- Install AWS CLI AWS CLI Installation Guide
- Configure credentials
Understanding IaC
- What is Infrastructure as Code?
- Why it matters in DevOps
Terraform ↔ AWS Connectivity
- Provider configuration
- Authentication via access keys
Practical Demo
- Created IAM user and group
- Attached policy for programmatic access
- Configured AWS CLI with credentials
- Used commands: terraform init, terraform plan, terraform apply
- Created EC2 instance using Terraform ▸ Used AMI image and named it Devmachine
- Validated Terraform configuration ▸ Used terraform validate to check syntax and logical consistency ▸ Optional: used JSON output for CI/CD integration

Initializes the working directory
Downloads provider plugins & Sets up backend configuration
Prepares .terraform folder if first-time setup or after changing providers/backends
& lockes the .teraform file (no changes can be made)

Verifies that your .tf files follow proper HCL (HashiCorp Configuration Language) syntax
Runs in the current working directory and checks all loaded modules
But Does not connect to cloud providers or check actual resource existence

Destroys all resources defined in your Terraform configuration
Everything tracked in the current state file (e.g., VMs, databases, networks)
Updates the state file to reflect that resources no longer exist (Note to undo re run terraform apply and recreate all)

Command	Explanation
terraform init	Initializes working directory, downloads providers/modules.
terraform plan	Previews changes without applying.
terraform plan -out=plan.tfplan	Saves plan to file for later apply.
terraform apply	Applies changes interactively.
terraform apply -auto-approve	Applies without confirmation (CI/CD use).
terraform destroy	Destroys all managed infra. Use carefully.
terraform destroy -target=aws_instance.web	Destroys only a specific resource.

Command	Explanation
terraform validate	Checks `.tf` files for syntax/config errors.
terraform fmt	Formats `.tf` files into canonical HCL style.
terraform fmt -check	Checks formatting only (CI-friendly).
terraform fmt -recursive	Formats files in subdirectories too.

Command	Explanation
terraform state list	Lists all resources tracked in state.
terraform state show <resource>	Shows attributes of a resource.
terraform state mv <src> <dst>	Moves/renames resource in state.
terraform state rm <resource>	Removes resource from state (infra stays).
terraform state pull	Downloads remote state as JSON.
terraform state push <file>	Uploads local state file to backend.
terraform import <resource> <id>	Imports existing infra into state.
terraform force-unlock <lock-id>	Releases a stuck state lock.

Command	Explanation
terraform workspace list	Lists all workspaces (dev, staging, prod).
terraform workspace show	Shows current workspace.
terraform workspace new <name>	Creates new workspace for environment separation.
terraform workspace select <name>	Switches workspace.
terraform workspace delete <name>	Deletes a workspace (not current).

Command	Explanation
terraform show	Displays current state or saved plan.
terraform show plan.tfplan	Shows saved plan file.
terraform output	Lists all output values.
terraform output -json	Outputs values as JSON.
terraform graph \| dot -Tpng > graph.png	Generates dependency graph.
terraform providers	Lists required providers.
terraform version	Shows installed version.