Top 45 Terraform / IaC Interview Questions & Answers (2026)

01 What is Infrastructure as Code (IaC)? 02 What is Terraform? 03 What is HCL (HashiCorp Configuration Language)? 04 What are the main Terraform commands? 05 What is Terraform state? 06 What is a Terraform Provider? 07 What is a Terraform Resource? 08 What are Terraform Variables? 09 What are Terraform Outputs? 10 What is a Terraform Module? 11 What is the difference between terraform plan and terraform apply? 12 What is the Terraform Registry? 13 What is Terraform remote state? 14 What is count and for_each in Terraform? 15 What is terraform.tfvars file? 16 What are Terraform data sources? 17 What is the lifecycle block in Terraform? 18 What is Terraform Cloud? 19 What is the difference between Terraform and Ansible? 20 What are Terraform workspaces?

01 What is the Terraform state locking mechanism? 02 How do you handle sensitive values in Terraform? 03 What are Terraform Provisioners and when should you avoid them? 04 What is Terraform import? 05 How do you structure Terraform code for large teams? 06 What is Terragrunt? 07 What are Terraform modules best practices? 08 What is the terraform_remote_state data source? 09 How do you test Terraform code? 10 What is Terraform drift and how do you handle it? 11 What is the Terraform provider version constraint syntax? 12 What is the Terraform lifecycle of a resource? 13 What is Packer and how does it relate to Terraform? 14 What is Atlantis and how does it automate Terraform? 15 How do you manage multiple environments in Terraform?

01 What is Terraform's provider development and custom providers? 02 What is Policy as Code with Sentinel in Terraform? 03 How does Terraform handle dependencies between resources? 04 What is the Terraform CDK (CDKTF)? 05 What are advanced Terraform state management operations? 06 How do you implement a CI/CD pipeline for Terraform? 07 What is Terraform's approach to secret management with Vault? 08 What are common Terraform anti-patterns and pitfalls? 09 How does Terraform handle provider authentication in different environments? 10 What is OpenTofu and how does it relate to Terraform?