Terraform Tutorial — State Best Practices

Following state best practices prevents data loss, security breaches, and team coordination issues.

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1. Always Use Remote State

Local state works for learning. For teams and production, use a remote backend:

terraform {
  backend "s3" {
    bucket         = "company-terraform-state"
    key            = "projects/web-app/terraform.tfstate"
    region         = "us-east-1"
    dynamodb_table = "terraform-locks"
    encrypt        = true
  }
}

Feature	Local	Remote (S3)
Team access	❌	✅
Locking	File-based	DynamoDB
Backup	Manual	S3 versioning
Encryption	❌	✅ SSE-S3/KMS
CI/CD	Difficult	Easy

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2. Enable Encryption

State contains secrets. Always encrypt at rest:

backend "s3" {
  encrypt = true  # SSE-S3 encryption
}

For stricter requirements, use KMS:

backend "s3" {
  encrypt        = true
  kms_key_id     = "arn:aws:kms:us-east-1:123456789:key/abc-def-123"
}

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3. Enable Versioning on the State Bucket

S3 versioning lets you recover previous state versions:

resource "aws_s3_bucket_versioning" "state" {
  bucket = aws_s3_bucket.state.id

  versioning_configuration {
    status = "Enabled"
  }
}

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4. Never Edit State Manually

Use Terraform commands instead:

Need	Wrong Approach	Right Approach
Rename resource	Edit JSON	terraform state mv
Remove resource	Delete from JSON	terraform state rm
Add existing resource	Write JSON	terraform import
View resource	Read JSON	terraform state show

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5. Add State Files to .gitignore

# .gitignore
*.tfstate
*.tfstate.*
.terraform/
*.tfvars     # if it contains secrets

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6. Separate State per Environment

Don’t put dev and prod in the same state file:

projects/
├── environments/
│   ├── dev/
│   │   ├── main.tf
│   │   └── backend.tf    ← key = "dev/terraform.tfstate"
│   ├── staging/
│   │   ├── main.tf
│   │   └── backend.tf    ← key = "staging/terraform.tfstate"
│   └── prod/
│       ├── main.tf
│       └── backend.tf    ← key = "prod/terraform.tfstate"
└── modules/
    └── vpc/

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What’s Next?

Practice what you’ve learned about state with the exercises.

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← State Commands Practice Exercises →