Terraform Associate Cheat Sheet

Terraform is declarative: you describe the desired state, not the steps

Applying the same config multiple times = same result

Plugin that translates HCL into API calls to the cloud provider

Managed unit of infrastructure (aws_instance, azurerm_vm...)

Reads data from existing infrastructure without creating it

Reusable set of resources (folder with .tf files)

Value exported from the state, accessible by parent modules or the user

Input parameter that allows reusing configurations

terraform.tfstate — maps HCL resources ↔ real resources

Never edit the state manually; use terraform state commands

Enables team collaboration and locking

Prevents corruption when multiple users apply simultaneously

terraform.tfstate.backup: automatic copy of the previous state

Hides the value in logs but it DOES persist in the state

(v1.10+): the value NEVER persists in state or plan

registry.terraform.io — public source for providers and modules

Declares which providers the project needs, with version constraints

~> 5.0 accepts 5.x but not 6.0

Pins exact provider versions, must be committed to git

Updates providers while respecting constraints

Directory where terraform is executed

Referenced with a module {} block from the root or another module

Local path, Terraform Registry, GitHub, S3, GCS

Downloads modules without initializing providers

Allow creating multiple instances of a resource/module

HashiCorp's official remote backend for state management and execution

Isolated environments with their own state

Policy-as-code framework integrated with HCP Terraform

Plans/applies run in the HCP cloud

Private module registry within the organization

DEPRECATED since v0.15.2 → use -replace

DEPRECATED since v0.15.4 → use plan -refresh-only

Opinionated: always produces the same result

.tfvars files are not loaded in child modules, only in the root

for_each requires a set or map; count requires a number

Creates an explicit dependency; Terraform resolves implicit dependencies automatically