Cheatsheets

Terraform Cheatsheet

Practical Terraform cheatsheet covering essential CLI commands, state management, import, workspaces, and key HCL patterns for variables, locals, outputs, dynamic blocks, and more. Perfect for daily IaC workflows.

7 Categories 12 Sections 28 Examples

Terraform HCL state management IaC variables modules

Core CLI Commands

Essential Terraform commands for initialization, validation, planning, applying, and destroying infrastructure.

Initialization & Validation

Commands to set up your Terraform workspace and check configuration validity.

Initializes the working directory, downloads providers and modules.

Code

terraform init

Output

1
Terraform has been successfully initialized!

Checks whether the configuration is valid (run after init).

Code

terraform validate

Output

1
Success! The configuration is valid.

Upgrades modules and providers to the latest allowed versions.

Code

terraform init -upgrade

Plan & Apply

Preview and execute infrastructure changes safely.

Shows what Terraform will create, change, or destroy.

Code

terraform plan

Saves the plan to a file for later apply.

Code

terraform plan -out=plan.tfplan

Applies a saved plan without prompting.

Code

terraform apply plan.tfplan

Applies changes without confirmation (use in CI/CD).

Code

terraform apply -auto-approve

Destroy

Safely remove all managed infrastructure.

Destroys all resources managed by Terraform.

Code

terraform destroy

Destroys only the targeted resource.

Code

terraform destroy -target=aws_instance.example

State Management

Commands for inspecting, manipulating, and synchronizing Terraform state.

State Commands

Core operations on the Terraform state file.

Lists all resources currently tracked in state.

Code

terraform state list

Shows detailed attributes of a specific resource in state.

Code

terraform state show aws_instance.example

Moves or renames a resource in state without recreating it.

Code

terraform state mv aws_instance.old aws_instance.new

Removes a resource from state (does not delete the actual infrastructure).

Code

terraform state rm aws_instance.example

Import & Taint

Bring existing resources under management and force recreation.

Imports an existing EC2 instance into Terraform state.

Code

terraform import aws_instance.example i-1234567890abcdef0

Replaces (recreates) a resource on the next apply (preferred over taint).

Code

terraform apply -replace=aws_instance.example

State Pull & Push

Synchronize local and remote state files.

Downloads the current remote state.

Code

terraform state pull

Uploads a local state file to the remote backend.

Code

terraform state push state.tfstate

Workspaces

Manage multiple isolated state environments (dev, staging, prod) with the same code.

Workspace Commands

Create, switch, list, and delete workspaces.

Creates and switches to a new workspace named 'dev'.

Code

terraform workspace new dev

Lists all workspaces (* indicates current).

Code

terraform workspace list

Switches to the 'prod' workspace.

Code

terraform workspace select prod

Deletes the 'dev' workspace (must not be current).

Code

terraform workspace delete dev

HCL Essentials

Core HashiCorp Configuration Language patterns used in every Terraform project.

Variables, Locals & Outputs

Input variables, computed locals, and exposed outputs.

Defines a variable with default, a local for reuse, and an output.

Code

variable "region" {
  type = string
  default = "us-east-1"
}

locals {
  common_tags = {
    Environment = var.environment
    ManagedBy   = "Terraform"
  }
}

output "vpc_id" {
  value       = aws_vpc.main.id
  description = "The ID of the VPC"
}

Data Sources

Read-only queries for external data.

Fetches the latest Ubuntu AMI for use in resources.

Code

data "aws_ami" "ubuntu" {
  most_recent = true
  owners      = ["099720109477"] # Canonical

  filter {
    name   = "name"
    values = ["ubuntu/images/hvm-ssd/ubuntu-focal-20.04-amd64-server-*"]
  }
}

Dynamic Blocks & for_each

Advanced HCL patterns for repeatable configuration.

for_each & Dynamic Blocks

Create multiple resource instances and nested blocks dynamically.

Creates one IAM user per item in the set using for_each.

Code

resource "aws_iam_user" "users" {
  for_each = toset(["alice", "bob"])
  name     = each.key
}

Generates multiple ingress blocks dynamically from a list/map.

Code

resource "aws_security_group" "example" {
  name = "example"

  dynamic "ingress" {
    for_each = var.ingress_rules
    content {
      from_port   = ingress.value.from_port
      to_port     = ingress.value.to_port
      protocol    = ingress.value.protocol
      cidr_blocks = ingress.value.cidr_blocks
    }
  }
}

Provider Configuration

Common patterns for configuring Terraform providers.

Provider Patterns

Declaring and configuring providers, including aliases.

Required providers block and basic + aliased configuration.

Code

terraform {
  required_providers {
    aws = {
      source  = "hashicorp/aws"
      version = "~> 5.0"
    }
  }
}

provider "aws" {
  region = var.region
}

# Aliased provider for multi-region
provider "aws" {
  alias  = "west"
  region = "us-west-2"
}

Debugging

Tools and techniques for troubleshooting Terraform issues.

Logging & Terraform Console

Enable detailed logs and test expressions interactively.

Enables the most verbose logging (TRACE, DEBUG, INFO, WARN, ERROR).

Code

TF_LOG=TRACE terraform plan

Interactive REPL to test expressions and functions.

Code

terraform console

Output

1
> join(", ", ["a", "b"])
2
"a, b"

Terraform Cheatsheet

Core CLI Commands

Initialization & Validation

Accessibility

Best Practices

Common Errors

Advanced Notes

Keywords

Initializes the working directory, downloads providers and modules.

Checks whether the configuration is valid (run after init).

Upgrades modules and providers to the latest allowed versions.

Plan & Apply

Accessibility

Best Practices

Common Errors

Advanced Notes

Keywords

Shows what Terraform will create, change, or destroy.

Saves the plan to a file for later apply.

Applies a saved plan without prompting.

Applies changes without confirmation (use in CI/CD).

Destroy

Best Practices

Common Errors

Advanced Notes

Keywords

Destroys all resources managed by Terraform.

Destroys only the targeted resource.

State Management

State Commands

Accessibility

Best Practices

Common Errors

Advanced Notes

Keywords

Lists all resources currently tracked in state.

Shows detailed attributes of a specific resource in state.

Moves or renames a resource in state without recreating it.

Removes a resource from state (does not delete the actual infrastructure).

Import & Taint

Best Practices

Common Errors

Advanced Notes

Keywords

Imports an existing EC2 instance into Terraform state.

Replaces (recreates) a resource on the next apply (preferred over taint).

State Pull & Push

Best Practices

Common Errors

Advanced Notes

Keywords

Downloads the current remote state.

Uploads a local state file to the remote backend.

Workspaces

Workspace Commands

Best Practices

Common Errors

Advanced Notes

Keywords

Creates and switches to a new workspace named 'dev'.

Lists all workspaces (* indicates current).

Switches to the 'prod' workspace.

Deletes the 'dev' workspace (must not be current).

HCL Essentials

Variables, Locals & Outputs

Best Practices

Common Errors

Advanced Notes

Keywords

Defines a variable with default, a local for reuse, and an output.

Data Sources

Best Practices

Common Errors

Advanced Notes

Keywords

Fetches the latest Ubuntu AMI for use in resources.

Dynamic Blocks & for_each

for_each & Dynamic Blocks

Best Practices

Common Errors