Top Terraform Interview Questions and Answers for Job Seekers 

What is Infrastructure as Code (IaC)?

 Infrastructure as Code is the practice of defining and managing infrastructure using machine-readable configuration files, rather than manual processes or scripts.

What is the difference between Terraform and other configuration management tools like Ansible or Puppet?

Terraform is focused on infrastructure as code, while tools like Ansible and Puppet are focused on configuration management.

What are the benefits of using Terraform?

Terraform enables automation, consistency, collaboration, cloud-agnosticism, scalability, and version control for infrastructure management.

What is a Terraform module?

A Terraform module is a collection of resources and configuration files that can be used to provision a particular type of infrastructure.

What is a provider in Terraform?

A provider is a plugin that enables Terraform to interact with a particular cloud provider, such as AWS or Azure.

What is a resource in Terraform?

A resource is a declarative description of a specific cloud infrastructure component, such as an EC2 instance or a database.

What exactly is a Terraform data source?

A data source is a read-only view of a specific cloud provider resource that may be used to retrieve information for usage in Terraform setup.

What is the distinction between a resource and a data source in Terraform?

A resource creates and manages infrastructure components, whereas a data source reads data from the cloud provider.

What exactly is a variable in Terraform?

A variable is a type of user-defined input that may be supplied to Terraform configuration files to enable dynamic configuration.

What is an output in Terraform?

An output is a value generated by Terraform during the infrastructure provisioning process, which can be used to pass information between different parts of the configuration.

What is the difference between input variables and output variables in Terraform?

Input variables are user-defined values passed to Terraform configuration files, while output variables are values generated by Terraform during the infrastructure provisioning process.

What is a state file in Terraform?

A state file is a record of the current state of the infrastructure, including information about resources and their configurations.

What is a backend in Terraform?

A backend is a storage location for the Terraform state file, such as a remote storage service or a version control system.

What is the difference between the local and remote states in Terraform?

The local state is stored on the user's local machine, while the remote state is stored in a backend, enabling collaboration and consistency across multiple users.

What is the syntax for defining a resource in Terraform?

The syntax for defining a resource in Terraform is as follows:

resource "resource_type" "resource_name" {

  attribute1 = "value1"

  attribute2 = "value2"

}

What is the syntax for defining a variable in Terraform?

The syntax for defining a variable in Terraform is as follows:

variable "variable_name" {

type = datatype

default = default_value

}

What is the syntax for defining an output in Terraform?

The syntax for defining an output in Terraform is as follows:

output "output_name" {

  value = value_expression

}

How can Terraform code be tested?

Unit testing, integration testing, and automated testing tools can all be used to test Terraform code. This ensures that the code works as intended and meets the infrastructure's needs.

How does Terraform handle numerous environments?

Terraform can handle many environments by combining workspaces and variable files. 

Who are Terraform's main competitors?

Ansible Packer Cloud Foundry Kubernetes are Terraform’s main competitors.

What are Terraform workspaces and how do you use them?

Terraform workspaces allow users to manage multiple instances of the same infrastructure within a single configuration. This can be used to manage environments such as development, staging, and production.

What is Terraform state locking and why is it important?

Terraform state locking prevents multiple users from modifying the state file at the same time, ensuring consistency and avoiding conflicts. This is important in collaborative environments where multiple users are working on the same infrastructure.

What is Terraform destroy and how do you use it?

Terraform destroy is a command that deletes all resources associated with a Terraform configuration, effectively tearing down the infrastructure.

What are Terraform modules and how do they work?

Terraform modules are reusable collections of resources and configuration files used to provision various types of infrastructure. They can be used to streamline configuration and provide consistency between projects.

What exactly is the distinction between Terraform modules and Terraform providers?

Terraform providers are plugins that allow Terraform to communicate with specific cloud providers, whereas Terraform modules are collections of resources and configuration files that can be used to provision certain types of infrastructure.

What exactly is a Terraform backend, and why is it necessary?

Terraform backend is a location where the Terraform state file is stored, allowing for collaboration and consistency across various users. It is critical because it assures that all users are working with the same state file.

What are Terraform data sources, and how do they work?

Terraform data sources give users read-only access to specific cloud provider services, allowing them to retrieve data for use in Terraform setups. They can be used to streamline configuration and provide consistency between projects.

What is the distinction between Terraform resources and Terraform data sources?

Terraform resources are used to build and maintain infrastructure components, whereas Terraform data sources are used to read data from the cloud provider.

What is a Terraform provider block, and how does it work?

Terraform provider block is a portion of the Terraform configuration file that defines the plugin that will communicate with the cloud provider. It includes configuration values like access keys and secret keys.

What is a Terraform provisioner and how does it work?

Terraform provisioner is a feature that allows users to run scripts or commands on newly created resources. This can be used to install applications, configure settings, and carry out other tasks.

What is a Terraform resource block and how do you use it?

Terraform resource block is a section of the Terraform configuration file that defines a specific cloud infrastructure component, such as an EC2 instance or a database.

What is the difference between a Terraform variable and a Terraform output?

Terraform variable is a user-defined input that can be passed to Terraform configuration files, while a Terraform output is a value generated by Terraform during the infrastructure provisioning process.

What is the purpose of Terraform modules output variables?

Terraform modules output variables can be used to pass information between different parts of the configuration, allowing users to simplify configuration and promote consistency across multiple projects.

What is the difference between a Terraform remote state and a Terraform local state?

A Terraform remote state is kept in a centralized place, such as an S3 bucket, whereas a local state is kept on the user's local system. 

What is the Terraform init command used for?

The Terraform init command sets up a Terraform setup with the necessary plugins, modules, and backends. It should be executed before any other Terraform commands.

What distinguishes Terraform from other tools for infrastructure as code?

In other words, Terraform may be used to manage infrastructure across many cloud providers because it is designed to be cloud-agnostic.

Moreover, it employs a declarative syntax that enables users to construct infrastructure components without defining the creation process.

How does a Terraform state file function? What is it?

Terraform state file is a JSON file that includes details about the resources that Terraform has produced. It makes it possible for Terraform to keep track of infrastructure changes and to manage resources across many settings.

What is the difference between Terraform apply and Terraform plan?

Terraform plan generates a preview of the changes that Terraform will make to the infrastructure, without actually making any changes. Terraform apply, on the other hand, applies those changes to the infrastructure.

How can you use Terraform to manage infrastructure across multiple cloud providers?

Terraform is designed to be cloud-agnostic, meaning that it can be used to manage infrastructure across multiple cloud providers.

To do so, users can define provider configurations for each cloud provider they wish to use, and then create resources in the appropriate provider using Terraform's declarative syntax.

Can I add policies to the pro or open-source versions of Terraform enterprise?

Terraform Policies cannot be added to the open-source description of Terraform Enterprise. The Enterprise Pro edition is the same. 

How do you manage complex deployments in Terraform?

Complex deployments in Terraform can be managed by breaking them down into smaller, modular components and using Terraform's dependency management features.

What is Terraform's "apply" step and how does it work?

The Terraform apply step applies changes to the infrastructure, creating or modifying resources as needed.

How do you manage Terraform state in a team environment?

Terraform state can be managed in a team environment using remote state, workspaces, and backend configuration.

What is Terraform's "provider" block and how do you use it?

The provider block in Terraform is used to define the cloud provider being used and the necessary credentials to access it.

How can you create custom modules in Terraform?

Custom modules in Terraform can be created by organizing reusable code into modules and using the module block to call them.

How do you test Terraform configurations?

Terraform configurations can be tested using automated testing tools such as Terratest or using manual testing with the Terraform validate command.

What is a data source in Terraform and how is it used?

A data source in Terraform provides information about an existing resource that can be used in a Terraform configuration.

What is the Terraform output block used for?

The Terraform output block is used to define values that can be shared between Terraform configurations.

How can Terraform be used to manage Kubernetes resources?

By leveraging the Kubernetes provider and establishing resources with the required YAML definitions, Terraform can be used to manage Kubernetes resources.

How can Terraform be used to manage AWS resources?

By using the Amazon provider and establishing resources with the right Terraform syntax, Terraform can be used to manage AWS resources.

How can you manage Terraform modules and dependencies?

Terraform modules and dependencies can be managed using version control tools such as Git, package managers such as Terraform Registry, or by manually downloading and installing modules.

How do you handle sensitive data in Terraform configurations?

Sensitive data in Terraform configurations can be handled using variables or by using a separate secure data store such as Vault or AWS Secrets Manager.

What is the difference between Terraform apply and Terraform refresh?

Terraform apply applies changes to the infrastructure, while Terraform refresh retrieves the current state of the infrastructure without making any changes.

What is the purpose of the Terraform plan output?

The Terraform plan output provides a detailed preview of the changes that Terraform will make to the infrastructure before they are applied.

What is the difference between Terraform and CloudFormation?

Terraform is a cloud-agnostic infrastructure management tool, while CloudFormation is specific to AWS.

What is the purpose of a Terraform backend?

The Terraform backend is responsible for storing the state file and providing locking functionality to prevent concurrent access to the state file.

By default, Terraform stores the state file locally, but a backend can be used to store the state remotely, such as in AWS S3 or HashiCorp Consul.

How do you manage sensitive data in Terraform?

Terraform provides several mechanisms for managing sensitive data, such as API keys, passwords, and certificates.

These include input variables, environment variables, and the Vault provider. The Vault provider allows Terraform to securely retrieve sensitive data from HashiCorp Vault.

What is the purpose of a Terraform provisioner?

A Terraform provisioner is a mechanism for running scripts or commands on a resource after it has been created or updated. Provisioners can be used for tasks such as configuring software on a new EC2 instance or running database migrations. 

Is Terraform suitable for on-premise infrastructure?

Yes, Terraform may be used to build on-premises infrastructure. 

What are the different Terraform versions that are supported?

• GitHub.com

• GitLab.com

• GitHub Enterprise

• CE and EE for GitLab

• Azure Server and Bitbucket Cloud Server and Services for DevOps