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- 01Getting Started
- 02What Is Terraform?
- 03Checking the Version with terraform version
- 04What Is Infrastructure as Code?
- 05What Is a Provider?
- 06Preparing Providers with terraform init
- 07What Is a Resource Block?
- 08Checking Syntax with terraform validate
- 09Formatting Code with terraform fmt
- 10Previewing Changes with terraform plan
- 11Building Infrastructure with terraform apply
- 12What Is tfstate?
- 13Viewing State with terraform show
- 14Listing Resources with terraform state list
- 15Inspecting One Resource with terraform state show
- 16What Are Variables?
- 17What Are Outputs?
- 18Reading Outputs with terraform output
- 19Tearing Down with terraform destroy
- 20What Is a Module?
- 21What Is a Workspace?
- 22Listing Workspaces with terraform workspace list
- 23Creating a Workspace with terraform workspace new
- 24Switching Workspaces with terraform workspace select
- 25Saving a Plan with terraform plan -out
- 26Applying a Saved Plan with terraform apply
- 27What Is State Locking?
- 28Listing Providers with terraform providers
- 29What Is terraform refresh?
- 30What Is a Remote Backend?
- 31Adopting Existing Resources with terraform import
- 32What Is depends_on?
- 33What Are for_each and count?
- 34Visualising Dependencies with terraform graph
- 35What Is State Drift?
- 36How to Think About Splitting Modules
- 37Hands-On: Building a Three-Tier Web Architecture with Terraform
What Is tfstate?
The state file is Terraform's record of what it has created and which real resource corresponds to each block in your configuration.
It is how Terraform knows, on the next run, that aws_instance.web already exists as instance i-0123… and needs changing rather than creating.
Running terraform show displays the current state in readable form, so you can see what Terraform believes exists.
A common stumble is committing the state file to Git. It contains resource details and often secrets, and concurrent edits corrupt it — it belongs in a remote backend.
In real work, state lives in S3 or Terraform Cloud with locking enabled, so a team can work on the same infrastructure safely.
🧑💻 You can type this command into the Terraform pseudo terminal to try it yourself (this page itself has no interactive terminal).