Interview Questions and Answers

Terraform is primarily an IaC tool that focuses on provisioning and managing infrastructure, while Ansible is a configuration management tool that automates software provisioning, configuration, and application deployment.

Terraform state is a snapshot of the infrastructure managed by Terraform. It is used to keep track of the resources created and their current state.

Terraform uses input variables and data sources to manage sensitive information securely. Secrets can be stored in environment variables or using a secret management tool.

'terraform plan' shows the execution plan without actually applying the changes, while 'terraform apply' executes the plan and makes the changes to the infrastructure.

To create a reusable Terraform module, define input variables, outputs, and use the module in other configurations. Organize the module in a separate directory with a 'main.tf' file.

Terraform automatically handles dependencies between resources. It analyzes the resource graph and provisions resources in the correct order based on dependencies.

'count' is used to create multiple instances of a resource, while 'for_each' is used for creating multiple instances based on a map or set of values.

The 'locals' block in Terraform is used to define local variables within a module. These variables are not exposed to the calling module and are only accessible within the module's scope.

Terraform provides a 'backend' configuration for state storage, and some backends support locking. By configuring the 'lock' option, Terraform can lock the state to prevent concurrent modifications.

Sensitive data like API keys can be stored securely using Terraform's sensitive input variable type or by using a secret management tool. Avoid storing sensitive information directly in configuration files.

Provisioners are used to execute scripts on a remote resource after creation, while 'null_resource' is a resource type that doesn't directly create infrastructure but can be used to trigger provisioners or other actions.

Terraform automatically masks sensitive information (like secrets) passed through environment variables in command output, making it more secure when dealing with secrets.

'terraform state mv' is used to move a resource instance from one Terraform state file to another. It allows restructuring or reorganizing resources in the state.

'terraform output' is used to display the values of output variables defined in the Terraform configuration. It helps retrieve information about the infrastructure after it's created.

A 'resource' block is used to define and create infrastructure resources, while a 'data' block is used to fetch and reference data that already exists, such as information from other resources.

In Terraform Cloud, you can use the 'sensitive' attribute for variables to mark them as sensitive. Terraform Cloud also provides a secure environment for managing sensitive information.