» Command: init

The terraform init command is used to initialize a working directory containing Terraform configuration files. This is the first command that should be run after writing a new Terraform configuration or cloning an existing one from version control. It is safe to run this command multiple times.

» Usage

Usage: terraform init [options] [DIR]

This command performs several different initialization steps in order to prepare a working directory for use. More details on these are in the sections below, but in most cases it is not necessary to worry about these individual steps.

This command is always safe to run multiple times, to bring the working directory up to date with changes in the configuration. Though subsequent runs may give errors, this command will never delete your existing configuration or state.

If no arguments are given, the configuration in the current working directory is initialized. It is recommended to run Terraform with the current working directory set to the root directory of the configuration, and omit the DIR argument.

» General Options

The following options apply to all of (or several of) the initialization steps:

  • -input=true Ask for input if necessary. If false, will error if input was required.

  • -lock=false Disable locking of state files during state-related operations.

  • -lock-timeout=<duration> Override the time Terraform will wait to acquire a state lock. The default is 0s (zero seconds), which causes immediate failure if the lock is already held by another process.

  • -no-color Disable color codes in the command output.

  • -upgrade Opt to upgrade modules and plugins as part of their respective installation steps. See the sections below for more details.

» Copy a Source Module

By default, terraform init assumes that the working directory already contains a configuration and will attempt to initialize that configuration.

Optionally, init can be run against an empty directory with the -from-module=MODULE-SOURCE option, in which case the given module will be copied into the target directory before any other initialization steps are run.

This special mode of operation supports two use-cases:

  • Given a version control source, it can serve as a shorthand for checking out a configuration from version control and then initializing the work directory for it.

  • If the source refers to an example configuration, it can be copied into a local directory to be used as a basis for a new configuration.

For routine use it is recommended to check out configuration from version control separately, using the version control system's own commands. This way it is possible to pass extra flags to the version control system when necessary, and to perform other preparation steps (such as configuration generation, or activating credentials) before running terraform init.

» Backend Initialization

During init, the root configuration directory is consulted for backend configuration and the chosen backend is initialized using the given configuration settings.

Re-running init with an already-initalized backend will update the working directory to use the new backend settings. Depending on what changed, this may result in interactive prompts to confirm migration of workspace states. The -force-copy option suppresses these prompts and answers "yes" to the migration questions. The -reconfigure option disregards any existing configuration, preventing migration of any existing state.

To skip backend configuration, use -backend=false. Note that some other init steps require an initialized backend, so it is recommended to use this flag only when the working directory was already previously initialized for a particular backend.

The -backend-config=... option can be used for partial backend configuration, in situations where the backend settings are dynamic or sensitive and so cannot be statically specified in the configuration file.

» Child Module Installation

During init, the configuration is searched for module blocks, and the source code for referenced modules is retrieved from the locations given in their source arguments.

Re-running init with modules already installed will install the sources for any modules that were added to configuration since the last init, but will not change any already-installed modules. Use -upgrade to override this behavior, updating all modules to the latest available source code.

To skip child module installation, use -get=false. Note that some other init steps can complete only when the module tree is complete, so it's recommended to use this flag only when the working directory was already previously initialized with its child modules.

» Plugin Installation

During init, the configuration is searched for both direct and indirect references to providers, and the plugins for the providers are retrieved from the plugin repository. The downloaded plugins are installed to a subdirectory of the working directory, and are thus local to that working directory.

Re-running init with plugins already installed will install plugins only for any providers that were added to the configuration since the last init. Use -upgrade to additionally update already-installed plugins to the latest versions that comply with the version constraints given in configuration.

To skip plugin installation, use -get-plugins=false.

The automatic plugin installation behavior can be overridden by extracting the desired providers into a local directory and using the additional option -plugin-dir=PATH. When this option is specified, only the given directory is consulted, which prevents Terraform from making requests to the plugin repository or looking for plugins in other local directories. Passing an empty string to -plugin-dir removes any previously recorded paths.

Custom plugins can be used along with automatically installed plugins by placing them in terraform.d/plugins/OS_ARCH/ inside the directory being initialized. Plugins found here will take precedence if they meet the required constraints in the configuration. The init command will continue to automatically download other plugins as needed.

When plugins are automatically downloaded and installed, by default the contents are verified against an official HashiCorp release signature to ensure that they were not corrupted or tampered with during download. It is recommended to allow Terraform to make these checks, but if desired they may be disabled using the option -verify-plugins=false.

» Running terraform init in automation

For teams that use Terraform as a key part of a change management and deployment pipeline, it can be desirable to orchestrate Terraform runs in some sort of automation in order to ensure consistency between runs, and provide other interesting features such as integration with version control hooks.

There are some special concerns when running init in such an environment, including optionally making plugins available locally to avoid repeated re-installation. For more information, see Running Terraform in Automation.