Top 125+ Terraform Interview Questions And Answers

Terraform is widely recognized as a leading infrastructure management tool, offering users the ability to manage resources safely, efficiently, and consistently. As a code tool, it enables users to define and manage cloud infrastructure in a declarative manner. Given its importance, companies like Terraform regularly seek proficient employees who can effectively utilize the tool. Job interviews for various positions within the company may vary, but a common thread is the exploration of candidates’ knowledge of Terraform, ranging from basic to advanced features. To aid in your interview preparation, here is a list of Terraform interview questions to help you familiarize yourself with the key concepts and features of the tool.

Terraform interview questions

What is Terraform?

What are the advantages of using Terraform?

What are the different types of resources in Terraform?

What is a provider in Terraform?

What is a module in Terraform?

What is state in Terraform?

How does Terraform handle dependencies between resources?

What is the difference between Terraform and Ansible?

What is the difference between Terraform and CloudFormation?

How does Terraform differ from traditional configuration management tools?

What is a variable in Terraform?

What is a data source in Terraform?

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

How does Terraform handle secrets and sensitive data?

What is the difference between Terraform apply and Terraform plan?

What is Terraform destroy?

How does Terraform handle version control?

What is the role of Terraform in infrastructure as code (IaC)?

How does Terraform handle drift detection?

How does Terraform handle resource deletion?

What is a backend in Terraform?

What is the role of a state file in Terraform?

What is the difference between Terraform state and configuration?

How does Terraform handle remote state?

What is Terraform Cloud?

How does Terraform Cloud differ from Terraform Enterprise?

Terraform interview questions for freshers

What are the common ways of installing Terraform?
Ans: Terraform can be installed using package managers like Homebrew, Chocolatey, or directly downloaded from the HashiCorp website.

What is a module registry in Terraform?
Ans: Module registry is a public registry that contains pre-built Terraform modules that can be easily imported and used in your own Terraform configurations.

What is a resource block in Terraform?
Ans: A resource block in Terraform describes a single infrastructure object or resource that you want to create or manage, such as a virtual machine, load balancer, or database.

What is the difference between Terraform state and configuration?
Ans: Terraform configuration defines the desired state of your infrastructure, while Terraform state keeps track of the actual state of your infrastructure.

What is the difference between a Terraform module and a provider?
Ans: A Terraform module is a collection of Terraform configuration files that can be reused across different projects, while a provider is a plugin that allows Terraform to interact with a specific cloud provider or service.

How does Terraform handle dependencies between modules?
Ans: Terraform uses input and output variables to establish dependencies between modules, allowing you to pass data and values between different parts of your infrastructure.

What is the difference between a variable and a data source in Terraform?
Ans: A variable is a parameter that can be defined in a Terraform configuration, while a data source is a way to retrieve data from an external source, such as an API or a file.

What is the purpose of a provider block in Terraform?
Ans: A provider block in Terraform is used to define the cloud provider or service that you want to interact with, as well as the credentials and settings required to access it.

How does Terraform handle infrastructure updates?
Ans: Terraform uses a process called plan and apply to manage infrastructure updates, which involves creating a plan that describes the changes to be made, and then applying those changes in a controlled and automated manner.

How does Terraform ensure consistency and reliability in infrastructure management?
Ans: Terraform uses declarative syntax and state management to ensure that the infrastructure is always consistent with the desired state, and can automatically rollback changes in case of errors or failures.

What is the difference between Terraform apply and Terraform refresh?
Ans: Terraform apply is used to create or update resources based on the current configuration, while Terraform refresh is used to update the Terraform state to match the current state of the infrastructure.

What is the role of a provider plugin in Terraform?
Ans: A provider plugin in Terraform is used to translate Terraform configuration into API calls that interact with the cloud provider or service, allowing Terraform to create and manage infrastructure resources.

How does Terraform handle resource dependencies?
Ans: Terraform uses implicit and explicit dependencies to handle resource dependencies, allowing you to specify the order in which resources should be created or updated.

What is the role of a backend in Terraform?
Ans: A backend in Terraform is used to store and manage the Terraform state, allowing you to collaborate with other team members, manage version control, and handle state locking.

What is the difference between Terraform state and backend?
Ans: Terraform state refers to the actual state of the infrastructure, while a backend refers to the storage and management of the Terraform state.

How does Terraform handle resource updates?
Ans: Terraform uses a process called resource replacement to update resources, which involves creating a new resource and then deleting the old resource, while preserving any data and metadata associated with the resource.

Terraform interview questions for 3 years experience

What is Terraform’s recommended way to manage infrastructure secrets?
Ans: Terraform recommends using environment variables or external secret storage systems like HashiCorp Vault to manage infrastructure secrets.

What is a Terraform workspace?
Ans: A Terraform workspace is a named state environment that allows you to manage multiple versions of the same infrastructure, such as development, staging, and production.

What is the difference between Terraform and Kubernetes?
Ans: Terraform is a tool for infrastructure provisioning and management, while Kubernetes is a container orchestration platform for managing containerized applications.

What is the difference between Terraform and Packer?
Ans: Terraform is a tool for infrastructure provisioning and management, while Packer is a tool for creating machine images for different platforms and environments.

What is the role of the Terraform graph command?
Ans: The Terraform graph command generates a visual representation of the Terraform configuration, showing the dependencies between resources and modules.

What is the difference between a Terraform configuration and a Terraform module?
Ans: A Terraform configuration defines the desired state of the infrastructure, while a Terraform module is a collection of Terraform configurations that can be reused across different projects.

What is a provisioner in Terraform?
Ans: A provisioner in Terraform is a resource that is responsible for executing scripts or commands on a remote resource, such as installing software or configuring settings.

What is a data block in Terraform?
Ans: A data block in Terraform is used to define a data source that retrieves information from an external source, such as an API or a file.

What is a backend configuration in Terraform?
Ans: A backend configuration in Terraform is used to define the storage and management of the Terraform state, including the type of backend, the backend URL, and the credentials required to access it.

How does Terraform handle resource deletion?
Ans: Terraform uses a process called destroy to delete resources, which involves removing the resource from the infrastructure and updating the Terraform state accordingly.

What is a provisioned resource in Terraform?
Ans: A provisioned resource in Terraform is a resource that has been created or updated using Terraform, and whose state is managed by Terraform.

What is the difference between Terraform and Chef?
Ans: Terraform is a tool for infrastructure provisioning and management, while Chef is a configuration management tool for managing the software and configurations of servers and applications.

What is a local-exec provisioner in Terraform?
Ans: A local-exec provisioner in Terraform is used to execute a command or script on the local machine after a resource has been created or updated.

What is the role of the Terraform init command?
Ans: The Terraform init command initializes a new or existing Terraform configuration, downloading the necessary provider plugins and setting up the backend configuration.

What is a count parameter in Terraform?
Ans: A count parameter in Terraform is used to create multiple instances of a resource, based on a numeric value or list of values.

What is the difference between Terraform and CloudFormation?
Ans: Terraform is a tool for infrastructure provisioning and management, while CloudFormation is a service provided by AWS for provisioning and managing AWS resources.

What is a null resource in Terraform?
Ans: A null resource in Terraform is a resource that does not create any infrastructure, but can be used to execute arbitrary code or scripts during the Terraform lifecycle.

Also check – WCF Interview Questions / Author Interview Questions

Terraform scenario based interview questions and answers

Scenario: You have a Terraform configuration file that creates an EC2 instance. How would you modify the configuration to add a security group to the instance?
Ans: I would modify the configuration by adding a resource block for the security group and then adding a reference to that security group in the resource block for the EC2 instance.

Scenario: You need to use a Terraform module to deploy an application to multiple environments. How would you parameterize the module to allow for different configurations in each environment?
Ans: I would parameterize the module by using input variables to define the configuration values for each environment, and then use conditionals or lookup functions to set those values based on the current environment.

Scenario: You are deploying an application to AWS using Terraform, and you need to create an S3 bucket to store the application files. How would you ensure that the S3 bucket is only accessible by authorized users?
Ans: I would use AWS IAM to define policies that restrict access to the S3 bucket based on the user’s role or permissions, and then reference those policies in the Terraform configuration.

Scenario: You have a Terraform configuration that deploys an EC2 instance, but you need to ensure that the instance is automatically terminated if it is idle for a certain period of time. How would you accomplish this?
Ans: I would use a combination of CloudWatch alarms and AWS Lambda functions to monitor the EC2 instance and automatically terminate it if it is idle for a specified period of time. I would then include the necessary configuration in the Terraform file.

Scenario: You have a Terraform configuration file that creates a VPC in AWS. How would you modify the configuration to add a private subnet to the VPC?
Ans: I would modify the configuration by adding a resource block for the private subnet, setting the appropriate CIDR block and availability zone, and then referencing the VPC in the subnet resource block.

Scenario: You need to deploy a Kubernetes cluster using Terraform. How would you ensure that the cluster is highly available?
Ans: I would use a combination of Kubernetes features, such as replica sets and stateful sets, along with Terraform configuration that defines multiple master nodes and load balancers, to ensure that the Kubernetes cluster is highly available.

Scenario: You need to deploy a database server using Terraform, and you want to ensure that the data is encrypted at rest. How would you accomplish this?
Ans: I would use the appropriate encryption options for the database server, such as AWS RDS encryption, and then include the necessary configuration in the Terraform file.

Scenario: You have a Terraform configuration that creates an autoscaling group in AWS, but you need to ensure that the instances in the group are evenly distributed across availability zones. How would you accomplish this?
Ans: I would use the “spread” parameter in the Terraform configuration to ensure that the instances in the autoscaling group are evenly distributed across availability zones.

Scenario: You have a Terraform configuration that creates an Elastic Load Balancer in AWS, but you need to ensure that the load balancer is configured to handle HTTPS traffic. How would you accomplish this?
Ans: I would add the appropriate SSL certificates and listener configuration to the Terraform configuration for the Elastic Load Balancer, to ensure that it can handle HTTPS traffic.

Terraform serves as a vital tool for managing cloud infrastructure, particularly favored by companies seeking to automate their infrastructure development and management processes. Working within such a company presents numerous career opportunities. However, to secure a position, thorough preparation is essential to effectively showcase your skills and expertise. Practicing the list of questions provided above can offer valuable insights into what to expect in a Terraform interview. By familiarizing yourself with these questions, you can increase your chances of success, ultimately bringing you closer to securing your dream job within the company.