Common commands
Last update：2025-01-14 17:48:36
Detailed explanation of common Terraform commands
Terraform is an open source tool developed by HashiCorp for building, changing, and versioning infrastructure securely and efficiently. This article will introduce some common commands of Terraform in detail to help you better understand and use Terraform.
1. Initialize the working directory
Order
terraform init
illustrate
The terraform init command is used to initialize the current directory. This command will do the following:
- Download and install the provider plugins defined in the Terraform configuration.
- Initialize any referenced modules.
- Checks whether a previously initialized state exists in the current directory.
Example
terraform init
After executing the above command, Terraform will download all providers defined in the configuration file and initialize the working directory.
2. Format the configuration file
Order
terraform fmt
illustrate
The terraform fmt command is used to format the Terraform configuration file to make it more readable. It automatically adjusts the spacing, alignment, and indentation in the file.
Example
terraform fmt
After executing this command, all .tf files in the current directory and its subdirectories will be formatted.
3. Verify the configuration file
Order
terraform validate
illustrate
The terraform validate command is used to verify whether the syntax and logic of the Terraform configuration file are correct. It does not communicate with any remote service, but only checks the configuration file itself.
Example
terraform validate
After executing this command, Terraform checks the configuration files for syntax errors and logic errors.
4. Generate and display execution plan
Order
terraform plan
illustrate
The terraform plan command is used to generate and display an execution plan that describes the operations that Terraform will perform on the infrastructure. This command does not actually perform any changes, but displays the changes in the plan for easy review by the user.
Example
terraform plan
After executing this command, Terraform displays the resources that will be created, modified, or destroyed.
5. Application configuration changes
Order
terraform apply
illustrate
The terraform apply command is used to apply configuration changes and actually perform operations to create, update, or destroy infrastructure. The command prompts the user to confirm the execution plan before the operation is performed.
Example
terraform apply
After executing this command, Terraform prompts the user to confirm the execution plan and applies the changes after the user confirms.
6. Destroy infrastructure
Order
terraform destroy
illustrate
The terraform destroy command is used to destroy the previously created infrastructure. It deletes all resources recorded in the current state file.
Example
terraform destroy
After executing this command, Terraform prompts the user to confirm the destruction plan and destroys all resources after the user confirms.
7. Check the current status
Order
terraform show
illustrate
The terraform show command is used to display the contents of the current Terraform state file, including the current status of all resources.
Example
terraform show
After executing this command, Terraform outputs the contents of the current state file.
8. List current resources
Order
terraform state list
illustrate
The terraform state list command is used to list all resources recorded in the current state file. This command is very useful for viewing the list of currently managed resources.
Example
terraform state list
After executing this command, Terraform will list all currently managed resources.
9. Output specific values
Order
terraform output
illustrate
The terraform output command is used to display the output variables defined in the configuration. Output variables are often used to pass information to other systems or as part of command line output.
Example
terraform output
After executing this command, Terraform displays the values of all output variables.
10. Get Module
Order
terraform get
illustrate
The terraform get command is used to download and update the modules referenced in the configuration. This command is very useful when using modules to ensure that all modules are downloaded correctly.
Example
terraform get
After executing this command, Terraform downloads and updates all modules.
11. Refresh status file
Order
terraform refresh
illustrate
The terraform refresh command is used to refresh the Terraform state file to reflect the actual infrastructure state. This command compares it with the current infrastructure and updates the state file.
Example
terraform refresh
After executing this command, Terraform updates the state file to match the actual infrastructure state.
With the above commands, you can efficiently manage and operate your infrastructure. Each command has more options and parameters, and you can view detailed help information through terraform -help . I hope this article will help you and help you better master the use of Terraform.