Migrate local Terraform state to S3

Single env §

Create a backend.tf file in your root directory with,

terraform {
  backend "s3" {
    bucket = "terraform-state-24282348899985669082079" # bucket must exist before applying this tf config
    key    = "terraform.tfstate"
    region = "us-east-1"
    encrypt = true
  }
}

Then migrate the existing state,

terraform init -migrate-state

Usage,

terraform plan
terraform apply

---

Multiple envs §

Have a backend.tf file in your root terraform directory with only the common values,

terraform {
  backend "s3" {
    bucket         = "your-company-terraform-state"
    region         = "us-east-1"  # Choose your region
    encrypt        = true
    
    # Key will be specified in the backend config files
  }
}

Within each of your environment directories have a .hcl file with the env specific variable values, like,

key = "staging/terraform.tfstate"

key = "prod/terraform.tfstate"

Then migrate your existing state,

terraform init -backend-config="envs/staging/backend-staging.hcl" -migrate-state

Then every time you change things,

terraform init -backend-config="envs/staging/backend-staging.hcl"
terraform plan -var-file="envs/staging/staging.tfvars"
terraform apply -var-file="envs/staging/staging.tfvars"