This project creates the following AWS resources:

• S3 bucket (for storing Terraform state files)
• VPC and subnets
• Internet Gateway
• Route tables
• EC2 instance
• Security groups

.
├── backend.tf       # Backend configuration
├── bucket.tf        # S3 bucket configuration
├── vpc.tf           # VPC and network configuration
├── ec2.tf           # EC2 instance configuration
├── variables.tf     # Variable definitions
└── terraform.tfvars # Variable values

1. Clean up existing resources (if needed)

   # Delete existing state files (if local)
   rm -f terraform.tfstate terraform.tfstate.backup
   
   # Delete existing .terraform directory
   rm -rf .terraform

2. Backend configuration

   • Modify backend.tf file to use local backend:

   terraform {
     required_version = ">= 1.0.0"
     
     # Use local backend
     backend "local" {}
   
     # Required providers
     required_providers {
       aws = {
         source  = "hashicorp/aws"
         version = "~> 5.0"
       }
     }
   }

3. Initialize Terraform

   terraform init

1. Create S3 bucket

   terraform apply -target=aws_s3_bucket.terraform_state

2. Why create S3 bucket first?

   • I created the S3 bucket first because it will be used as the backend for storing the Terraform state file.
   • This approach solves a "chicken and egg" problem: I needed the S3 bucket to store the state file, but I can't create the bucket if we're already using it as a backend.
   • By creating the bucket first with a local backend, then migrating to the S3 backend, I ensure a smooth transition without state file conflicts.

3. Verify S3 bucket settings

   • Server-side encryption enabled
   • Public access blocked
   • Versioning enabled

1. Change backend configuration

   • Modify backend.tf file to use S3 backend:

   terraform {
     required_version = ">= 1.0.0"
     
     # Use S3 backend
     backend "s3" {
       bucket         = "gunsu-private-bucket-8926937-state"
       key            = "terraform.tfstate"
       region         = "us-east-1"
       encrypt        = true
     }
   
     # Required providers
     required_providers {
       aws = {
         source  = "hashicorp/aws"
         version = "~> 5.0"
       }
     }
   }

2. Migrate state file

   terraform init -migrate-state

1. Create all resources

   terraform apply

2. Verify created resources

   • Check in AWS Console that the following resources have been created:
     • S3 bucket (gunsu-private-bucket-8926937-state)
     • terraform.tfstate file in the S3 bucket
       
       
     • VPC (gunsu-vpc)
       
       
     • Public subnet (terraform-project-public-subnet)
       
       
     • Internet Gateway (terraform-project-igw)
       
       
     • Route table (terraform-project-public-rt)
       
       
     • EC2 instance (terraform-project-web-server)
       
       
     • Security group (terraform-project-ec2-sg)
       
       

1. Delete all resources

   terraform destroy

2. S3 bucket deletion issues

   • S3 bucket must be empty before deletion.
   • If versioning is enabled, all versions of objects must be deleted.

1. IAM permission issues
   • Problem: Cannot create resources due to insufficient IAM permissions.
   • Solution: Add necessary permissions in AWS IAM console.
   • Required permissions: s3:CreateBucket, ec2:CreateVpc, etc.