TF-004 Practice Test 2 — 10 Questions

Question 1

A junior engineer is asked to review a Terraform configuration that defines a module from the Terraform Registry. In which files are the descriptions of the module’s inputs and outputs typically found?

Choose an answer to begin — your selection is scored in the full session.

Accepted Answer

variables.tf. In Terraform modules, input variables are declared in `variables.tf` with `description` arguments to document their purpose, and output values are declared in `outputs.tf` with `description` arguments. Therefore, descriptions of both inputs and outputs are found in these two files. Neither file alone describes both; the question's phrasing implies consideration of both files, making both B and C correct.

Answer

versions.tf

Answer

main.tf

Question 2

An organization uses Terraform with remote state stored in S3 and DynamoDB for state locking. During a plan, they receive the error: 'Error acquiring the state lock: ConditionalCheckFailedException: The conditional request failed'. What is the most likely cause?

Accepted Answer

Another Terraform process is currently running and holds the state lock.. The error 'ConditionalCheckFailedException' occurs when DynamoDB's conditional put operation fails, which happens when a lock item already exists in the DynamoDB table. This indicates another Terraform process currently holds the state lock, preventing concurrent operations. Terraform uses DynamoDB's conditional writes to ensure only one process can acquire the lock at a time.

Answer

The state file in S3 is corrupted.

Answer

The DynamoDB table is not configured with a primary key named LockID.

Answer

The S3 bucket does not have versioning enabled.

Question 3

Refer to the exhibit. A team is troubleshooting a Terraform deployment. What information can be inferred from this state file?

Accepted Answer

There is one EC2 instance of type t2.micro with a dependency on a security group.. The state file explicitly shows a resource of type `aws_instance` with `instance_type = "t2.micro"` and a `depends_on` meta-argument referencing `aws_security_group.example`. This indicates that Terraform recorded the EC2 instance as created with a t2.micro type and that it has a formal dependency on a security group resource, ensuring the security group is created before the instance during apply.

Answer

The Terraform version is outdated and must be upgraded.

Answer

The instance ID is invalid and needs to be recreated.

Answer

The security group dependency was not applied.

Question 4

A team uses Terraform with remote state in an S3 backend and DynamoDB for state locking. A user runs 'terraform apply' and receives the error: 'Error acquiring the state lock'. The lock info shows a lock ID and caller. What is the best immediate course of action?

Accepted Answer

Check if another Terraform process is running; if not, use 'terraform force-unlock' with the lock ID.. The error indicates a state lock is held, typically by another Terraform process or a stale lock. The best immediate course is to verify no other process is running (e.g., via 'ps' or task manager), then use 'terraform force-unlock -lock-id=<LOCK_ID>' to release the lock. This is the safe, documented procedure that preserves the state file and DynamoDB lock table integrity.

Answer

Delete the state file from S3 and re-run apply.

Answer

Manually delete the DynamoDB lock table item.

Answer

Wait for 15 minutes and re-run apply.

Question 5

An engineer modifies a Terraform configuration by increasing the instance_count for an AWS EC2 resource from 2 to 5. After running terraform plan, which change will be displayed?

Accepted Answer

Three new resources will be created, two unchanged.. Terraform's `instance_count` meta-argument uses a count-based resource management strategy. When the count increases from 2 to 5, Terraform treats the existing resources (index 0 and 1) as unchanged and plans to create three new resources (indices 2, 3, and 4). No in-place updates or destructions occur because the existing resources' configurations remain identical.

Answer

One new resource will be created and two modified.

Answer

Two existing resources will be destroyed and five new created.

Answer

All five resources will be updated in-place.

Question 6

Refer to the exhibit. A developer runs `terraform plan -out=tfplan` and then `terraform apply "tfplan"`. During apply, network fails and apply is interrupted. The developer then runs `terraform apply` again (without a plan file). What will happen?

Accepted Answer

It will create a new plan and apply only the changes that are still needed. When `terraform apply` is run without a plan file, Terraform automatically creates a new plan based on the current state and configuration, then applies only the changes that are still needed. Since the previous apply was interrupted, the state file reflects the partial progress, and the new plan will detect any remaining resources that still need to be created, updated, or destroyed, ensuring idempotent behavior.

Answer

It will automatically use the previously saved plan file `tfplan`

Answer

It will fail because the state is locked from the previous apply

Answer

It will resume the previous apply from where it left off

Question 7

A module 'web_app' defines an input variable 'instance_count' with type = number and a validation block ensuring it is between 1 and 10. What happens if a user sets instance_count = 0?

Accepted Answer

Terraform returns an error during validation and stops execution.. HashiCorp Terraform validates input variables against their declared type and any validation blocks before applying configuration. When `instance_count = 0` is set, the validation block's condition `var.instance_count >= 1 && var.instance_count <= 10` evaluates to `false`, causing HashiCorp Terraform to halt with an error during the `terraform plan` or `terraform validate` phase, preventing any further execution.

Answer

Terraform applies the module with zero instances, as a value of 0 is allowed.

Answer

Terraform ignores the validation if the variable is explicitly set.

Answer

Terraform uses the default value for instance_count from the module.

Question 8

You are a platform engineer at a growing startup. The company currently manages infrastructure manually by SSH-ing into servers to install packages and update configurations. As the team grows, this approach has led to frequent configuration drift, inconsistent environments, and manual errors. Deploying a new environment takes several days and requires detailed runbooks. The CTO has asked you to propose a solution that improves consistency, reduces deployment time, and enables version control of infrastructure. You are evaluating Infrastructure as Code (IaC) tools like Terraform. Which course of action best addresses the CTO's requirements?

Accepted Answer

Adopt Terraform to define all infrastructure as code, store configurations in a Git repository, and use a CI/CD pipeline to apply changes automatically.. Terraform directly addresses the CTO's requirements by enabling infrastructure as code (IaC), which ensures consistent, repeatable deployments through declarative configuration files stored in Git for version control. Using a CI/CD pipeline to automatically apply changes eliminates manual SSH errors, reduces deployment time from days to minutes, and prevents configuration drift by enforcing a single source of truth for infrastructure state.

Answer

Improve SSH key management and use configuration management tools like Ansible to apply changes.

Answer

Migrate all applications to containers and use Kubernetes for orchestration.

Answer

Create more detailed runbooks and require peer review for all manual changes.

Question 9

A team uses a remote state backend with partial configuration. They have a `backend` block with only the `bucket` attribute, and the rest of the backend configuration is provided via CLI during `terraform init`. Which of the following best describes the purpose of partial configuration?

Accepted Answer

It allows sensitive backend configuration to be provided dynamically, avoiding hardcoding.. Partial configuration in Terraform remote state backends allows you to split backend settings between the `backend` block in your configuration and dynamic inputs provided at `terraform init` time. This is especially useful for sensitive values like access keys or secret tokens, which can be supplied via CLI flags, environment variables, or interactive prompts, thereby avoiding hardcoding them in version-controlled files. Option D correctly identifies this primary purpose of enhancing security and flexibility.

Answer

It reduces the number of files needed for configuration.

Answer

It is required when using Terraform Cloud.

Answer

It enables state locking.

Question 10

What is the purpose of the `terraform state list` command?

Accepted Answer

List all resources in the current state file. `terraform state list` lists all resources currently tracked in the Terraform state file, providing their resource addresses. Option B correctly describes this. Option A is incorrect because `terraform state list` does not show planned resources; that is the role of `terraform plan`. Option C lists resources from configuration (not from state), D lists workspaces, and E lists providers.

Answer

List all resources that would be created by the current plan

Answer

List all resources defined in the Terraform configuration

Answer

List all available workspaces

Answer

List all providers used in the configuration