HashiCorp Terraform-Associate-003 - HashiCorp Certified: Terraform Associate (003) (HCTA0-003)

Sensitive values such as API tokens should be stored in a secure way, either in Terraform Cloud variables marked as sensitive or in HashiCorp Vault. Storing secrets in version control systems or plaintext files is not recommended.

Module Versioning: To specify a version in a module block for modules in theTerraform Registry, you add the version attribute, e.g., version = "1.0.0".

Terraform Registry Support: The public registrysupports versioningby enabling semantic constraints, allowing users to define specific versions compatible with their infrastructure requirements.

Refer to themodule versioning documentationin Terraform’s official registry guide.

Option C is the correct way to configure multiple providers in a Terraform configuration. Each provider block must have a name attribute that specifies which provider it configures2. The other options are either missing the name attribute or using an invalid syntax.

C (✅Correct)– If changes require aresource replacement(e.g., changing an immutable attribute like instance type), Terraform willdestroy and recreate the resource.

E (✅Correct)– Terraform only appliesthe configuration in the current directory or workspace.

The -replace flag is used with the terraform apply command when there is a need to explicitly force Terraform to destroy and then recreate a specific resource during the next apply. This can be necessary in situations where a simple update is insufficient or when a resource must be re-provisioned to pick up certain changes.

This is the scenario that poses a challenge for this team, if they adopt AWS CloudFormation as their standardized method for provisioning public cloud resources, as CloudFormation only supports AWS services and resources, and cannot be used to provision infrastructure on other cloud platforms such as Azure.

You should use the force-unlock command when automatic unlocking failed. Terraform will lock your state for all operations that could write state, such as plan, apply, or destroy. This prevents others from acquiring the lock and potentially corrupting your state. State locking happens automatically on all operations that could write state and you won’t see any message that it is happening. If state locking fails, Terraform will not continue. You can disable state locking for most commands with the -lock flag but it is not recommended. If acquiring the lock is taking longer than expected, Terraform will output a status message. If Terraform doesn’t output a message, state locking is still occurring if your backend supports it. Terraform has a force-unlock command to manually unlock the state if unlocking failed. Be very careful with this command. If you unlock the state when someone else is holding the lock it could cause multiple writers. Force unlock should only be used to unlock your own lock in the situation where automatic unlocking failed. To protect you, the force-unlock command requires a unique lock ID. Terraform will output this lock ID if unlocking fails. This lock ID acts as a nonce, ensuring that locks and unlocks target the correct lock. The other situations are not valid reasons to use the force-unlock command. You should not use the force-unlock command if you have a high priority change, if apply failed due to a state lock, or if you see a status message that you cannot acquire the lock. These situations indicate that someone else is holding the lock and you should wait for them to finish theiroperation or contact them to resolve the issue. Using the force-unlock command in these cases could result in data loss or inconsistency. References = [State Locking], [Command: force-unlock]

You can develop a custom provider to manage its resources using Terraform, as Terraform is an extensible tool that allows you to write your own plugins in Go language. You can also publish your custom provider to the Terraform Registry or use it privately.

Child modulesdo not automatically inheritvariables from the parent module.

To pass values from theparent moduleto thechild module, you mustexplicitly define input variablesin the child module and pass them in the parent module.

Example:

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module "example" {

source = "./child_module"

var1 = "value"

}

Official Terraform Documentation Reference:

Passing Variables to Modules

The terraform import command allows Terraform to takeexistinginfrastructure andbring it under Terraform’s management.

A (terraform get)is incorrect because it is used to fetch modules.

B (terraform refresh)is incorrect because it only updates Terraform's state to match the infrastructure but does not import resources.

D (terraform init)is incorrect because it only initializes the Terraform working directory.

Official Terraform Documentation Reference:

terraform import - HashiCorp Documentation