HashiCorp Certified: Terraform Associate Interview Questions

HashiCorp Certified: Terraform Associate Exam are for those candidates or professionals working as Cloud Engineers who want to specialize in operations, IT, or development. The certification also focuses on the fundamental concepts and skills connected with HashiCorp Terraform, an open-source project. Candidates should additionally prepare for this test by having professional experience with Terraform in a production context, while completing the exam objectives in a personal demo setup may suffice. You’ll learn more about enterprise features as well as things that aren’t possible with open-source software.

1.) What exactly do you mean when you say Terraform?

HashiCorp’s Terraform is an open-source communication as a system software tool. It’s a tool for creating, modifying, and versioning transportation in a safe and professional manner. Terraform can guide established and well-known service providers as well as in-house solutions.

2.) What are the advantages of Terraform for DevOps?

The following are some of the benefits of using Terraform for DevOps:

Not only can it manage configurations, but it can also orchestrate them (like Ansible and Puppet).
Almost all popular cloud providers, such as AWS, Azure, GCP, DigitalOcean, and others, give excellent assistance.
Manages the configuration of a dynamic (immutable) infrastructure with ease.
Provide an immutable architecture that allows for easy configuration modifications.
HCL (HashiCorp configuration language) is used, which is a simple language to learn and understand.

It’s simple to move from one provider to the next.
Installation is simple.

3.) What is the definition of Terraform init?

Terraform uses the command terraform init to start the code. The working directory containing Terraform configuration files is initialised using this command. It is safe to use this command more than once.

The init command can be used to do the following:

Backend Initialization
Plugin Installation
Child Module Installation

4.) What are some of Terraform’s main competitors?

Here are a few examples:

Ansible
Kubernetes
Cloud Foundry
Packer

5.) What exactly is a Terraform provider?

Terraform is a tool for managing and informing infrastructure resources like physical machines, virtual machines, network switches, and containers. A provider is in charge of intelligent API interactions and resource disclosure. Terraform works with a wide range of cloud providers.

6.) What is Terraform and how does it work?

Terraform produces an implementation plan, specifies what it will do to achieve the desired state, and then executes the plan to build the infrastructure stated. Terraform is capable of determining what changed as the configuration changes and generating incremental execution plans that are practical.

7.) What are some of the most important characteristics of Terraform?

Here are a few examples:

Change Automation Resource Graph Infrastructure as code Execution Plan

8.) What is the definition of IAC?

The concept “Infrastructure as Code” is abbreviated as IaC. IaC is a technique that allows developers to run and provision computer data centers mechanically rather than going through a physical process. Terraform, for example, is an example of an IaC tool.

9.) How can I see what version of Terraform I have installed?

The terraform -version command can be used to determine the version of the command we are running.

10.) Describe the Terraform core’s operation.

The terraform core examines configuration monitoring and performs analysis and evaluations based on the configuration. It keeps track of the versions (current and previous) and compares them before displaying the results on the terminal.
Terraform core is mostly fed by two sources:
Terraform Configuration — It manages infrastructure details.
Terraform state — It maintains track of the status of the infrastructure.

11.) What are the main characteristics of Terraform?

The following are Terraform’s primary features:

Terraform’s high-level configuration language is used to specify your infrastructure in declarative configuration files that are human-readable.
You may now generate a blueprint that is editable, shareable, and reusable.
Before making any infrastructure changes, Terraform develops an execution plan that outlines what it will do and asks for your approval. Before Terraform produces, upgrades, or destroys infrastructure, you can evaluate the changes.
Terraform generates a resource graph while developing or changing non-dependent resources at the same time. Terraform can now generate resources as rapidly as possible while also providing you with more infrastructure information.
Terraform’s change automation allows you to make complex changes.

The automation of change feature in Terraform allows you to apply complex changesets to your infrastructure with little to no human input. Terraform is aware of this.

12.) What are some of Terraform’s applications?

Terraform’s use cases are as follows:

How to Create a Heroku App:
Heroku is a well-known platform as a service for hosting web applications (PaaS). Developers start by building an app, then add features like a database or an email service. One of the most appealing features is the flexibility to scale the number of dynos or workers as needed. Most non-trivial applications, on the other hand, quickly require a large number of add-ons and external services.

Terraform may be used to codify a Heroku application’s setup, ensuring that all required add-ons are there, but it can also go beyond, such as configuring DNSimple to configure a CNAME or Cloudflare as the app’s CDN. Best of all, Terraform can do all of this without using a web interface in around 30 seconds.

Self-Service Clusters: A centralized operations team monitoring a big and growing infrastructure becomes extremely difficult at a given organizational level. Implementing “self-serve” infrastructure, which allows product teams to manage their own infrastructure using tooling given by the central operations team, becomes more appealing.
Terraform configuration can be used to track how a service is built and scaled. You can then share these settings with the rest of your organisation, allowing client teams to administer their services using Terraform.

Environments can be created quickly: It’s customary to have a staging or quality assurance environment in addition to a production environment. These locations are miniature copies of their production counterparts, and they’re used to test new shows before they’re shown to the general public. Maintaining an up-to-date staging environment gets increasingly difficult as the production environment grows larger and more involved.
Terraform may be used to codify and share the production environment with staging, QA, and development. These settings can be used to quickly create new testing environments that can be swiftly discarded. By allowing parallel habitats to be formed and destroyed on the fly, Terraform can help to lessen the difficulties of managing them.

Resource schedulers: As large-scale infrastructures grow, static application assignment to machines becomes more difficult. Borg, Mesos, YARN, and Kubernetes are just a few of the schedulers that can help. Docker containers, Hadoop, Spark, and a variety of other software applications may all be dynamically scheduled using these.
Terraform isn’t just for physical providers like Amazon Web Services. Terraform can request resources from resource schedulers since they can be thought of as providers. Terraform may now work in stages, such as deploying the physical infrastructure that powers the schedulers and provisioning the scheduled grid.

Software demonstrations: In today’s world, software is becoming increasingly networked and distributed. Although virtualized demo environments may be constructed with tools such as Vagrant, showing software on real infrastructure that closely resembles production environments is still difficult.
On cloud providers like AWS, software authors can use a Terraform configuration to design, provision, and bootstrap a demo. End customers may easily demo the application on their own infrastructure, and settings like cluster size can be changed to test tools at any scale.

13.) Explain how to utilise Terraform CLI and provide a list of fundamental CLI commands?

The terraform command provides a command-line interface to Terraform, which accepts a range of subcommands such as terraform init and terraform plan.

Commands that are commonly used:

init terraform: Make sure your working directory is ready for future commands.
plan for terraforming: Show adjustments required by the current terraform configuration: Infrastructure is created or updated.
demolish the terraform: Destroy any infrastructure that has already been built.

14.) What role does Terraform play in the discovery of plugins?

Terraform interprets configuration files in the operational directory with the authority “Terraform init.” Terraform then determines which plugins are required and searches for them in various locations. Terraform also downloads more plugins from time to time. Then it chooses which plugin versions to use and creates a security device file to ensure that Terraform uses the same versions of plugins.

15.) Is it possible to add policies to Terraform enterprise’s open-source or pro versions?

You can’t add policies to Terraform Enterprise’s open-source description. The Enterprise Pro version is in the same boat. Terraform Enterprise’s best version could only communicate with the lookout policies.

16.) In Terraform, how do you define modules?

A module in Terraform is a jug for several resources that are utilised collectively. Every Terraform that includes resources referenced in.tf files requires the root module.

17.) What are the different options for locking Terraform module versions?

The terraform module registry can be used as a source, and the attribute’version’ in the module can be specified in a terraform configuration file. If you’re utilising the GitHub repository as a source, you’ll need to use the ‘? ref’ command to specify the branch, version, and query string.

18.) What exactly do you mean when you say Terraform cloud?

Terraform Cloud is a collaboration tool for teams using Terraform. It offers easy access to shared state and secret data, access controls for approving infrastructure modifications, a private registry for sharing Terraform modules, full policy controls for managing the contents of Terraform configurations, and more.

19.) In Terraform, how do you define a null resource?

The null resource follows the standard resource lifetime but doesn’t do anything special. The trigger argument allows you to specify a subjective set of values that will source the reserve to be replaced if they are misrepresented.

The null resource’s main application is as a do-nothing container for a provisioner’s arbitrary operations.

20.) Is it possible to use Terraform for on-premise infrastructure?

Terraform can be used to build on-premise infrastructure. There are numerous options available. You can select any one of them that best matches your needs. Many people create their own client Terraform providers; all they need is an API.

21.) What is the purpose of the following command?

terraform -version – to see what version of terraform is installed.
Terraform fmt is used to rewrite configuration files in canonical styles and format Terraform providers is used to display information about providers that are currently active in the configuration.

22.) Give a list of Terraform versions that are supported.

GitHub.com
GitLab.com
GitHub Enterprise is a business version of GitHub.
CE and EE versions of GitLab
Azure DevOps Server and Services Bitbucket Cloud and Server

23.) In the context of Terraform, explain the command terraform validate.

The terraform validate tool examines a directory’s configuration files, focusing just on the configuration and ignoring any other services such as remote state, provider APIs, and so on. Validate looks at a configuration to see if it’s syntactically correct and internally consistent, regardless of variables or current state. As a result, it’s best for checking the validity of attribute names and value types in general reusable modules.

This command can be used as a post-save check in a text editor or a test step in a continuous integration system for a reusable module.
terraform validate [options] is the syntax.

24.) Mention some of the version control tools that Terraform supports.

Terraform supports the following version control tools:

GitLab EE
Bucket Cloud
GitHub
GitLab CE

25.) How would you recover from a failed Terraform application?

You can save your configuration in version control and commit each change, then utilise the functionality of your version control system to revert to an earlier configuration if necessary. You must always recommit the prior version code in order for it to become the new version in the version control system.

26.) What exactly do you mean by Terragrunt, and what are examples of its applications?

Terragrunt is a lightweight wrapper that adds extra features for keeping your setups DRY, maintaining remote states, and working with numerous Terraform modules.

Use cases:

Keep your Terraform code DRY
Maintain the remote state settings. DRY
Keep your CLI flags DRY

Run Terraform commands on several modules at the same time.
Work with numerous Amazon Web Services (AWS) accounts

27.) What procedures should be taken to make a high-level object from one module available to the other module?

The steps to make an object from one module available to the other module at a high level are as follows:

A resource configuration must first declare an output variable. The scope of local and to a module will not be declared until you define resource configuration details.
Now you must declare module A’s output variable so that it can be utilised in the setups of other modules. You should establish a fresh new and up-to-date key name, with a value that is equal to the output variable of module A.

You must now create a file named variable.tf for module B. Create an input variable with the exact same name as the key you defined in module B inside this file. This variable permits the resource’s dynamic setting in a module. Replicate the process to make this variable available to other modules as well. This is because the scope of the variable established here is limited to module B.

28.) What is State File Locking, and how does it work?

Terraform’s state file locking mechanism prevents multiple users from performing the same operation on the same state file by blocking operations on that file. After one user’s lock is released, any other user who has taken a lock on that state file can operate on it. This prevents the state file from being corrupted. The obtaining of a lock on a state file in the backend is a backend operation. If acquiring a lock on the state file takes longer than intended, you will receive a status message as an output.

29.) In Terraform, what is a Remote Backend?

Terraform’s remote backend stores terraform’s state and can also conduct operations in the terraform cloud. terraform commands such as init, plan, apply, destroy (terraform version >= v0.11.12), get, output, providers, state (sub-commands: list, mv, pull, push, rm, show), taint, untaint, validate, and many others can be run from a remote backend. It can be used with a single or several remote terraform cloud workspaces. You can utilise terraform cloud’s run environment to conduct remote operations like terraform plan or terraform apply.

30.) What does it mean to have a tainted resource?

Tainted resources are ones that must be deleted and rebuilt when the next apply command is sent. Nothing happens on infrastructure when you mark a resource as contaminated, but the state file is updated with this information (destroy and create). After tainting a resource, terraform plan out will display that the resource will be destroyed and regenerated, and the alterations will be applied when the next apply occurs.

31.) With the help of terraform, how are callbacks on Azure used?

The terraform uses Azure Event Hub to perform Azure callbacks. It aids in the completion of tasks such as sending a callback to the system and other occurrences. This functionality is already included in Terraform AzureRM to make the process easier.

32.) What does it mean to have a tainted resource?

33.) With the help of terraform, how are callbacks on Azure used?

34.) How to Avoid a Duplicate Resource Error?

Depending on the situation and the necessity, it can be accomplished in one of three ways.

1) By destroying the resource, the Terraform code will no longer manage it.
2) By removing resources from APIs
3) Importing action will also aid in resource elimination.

35.) Explain the main terraform’s workflow.

Terraform’s primary workflow consists of three steps:

Write – Write code to create infrastructure.
Plan ahead of time to see how the changes will seem before implementing them.
Create a repeatable infrastructure by following the steps below.