Drift detection in CI/CD in Terraform - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is drift detection in the context of CI/CD?

Drift detection is the process of identifying differences between the desired infrastructure state defined in code and the actual state running in the cloud or environment.

beginner

Why is drift detection important in Terraform-based CI/CD pipelines?

It ensures that the infrastructure matches the code, preventing unexpected changes or errors caused by manual updates or external modifications.

beginner

Which Terraform command is commonly used to detect drift?

The command terraform plan compares the current infrastructure state with the configuration files and shows any differences.

intermediate

How can drift detection be automated in a CI/CD pipeline?

By running terraform plan as part of the pipeline and failing the build if unexpected changes are detected.

beginner

What is a common real-life analogy for drift detection?

It's like checking your house keys against a checklist before leaving to make sure nothing is missing or changed unexpectedly.

What does Terraform's terraform plan command do in drift detection?

A Shows differences between code and actual infrastructure

B Deletes all infrastructure

C Deploys new infrastructure without checking

D Only formats the code files

terraform plan compares the current infrastructure state with the configuration and shows any differences, helping detect drift.

Why should drift detection be part of a CI/CD pipeline?

A To send notifications to users

B To speed up code compilation

C To backup code files

D To automatically detect and prevent unexpected infrastructure changes

Including drift detection in CI/CD helps catch infrastructure changes that don't match the code, avoiding errors.

What happens if drift is detected during a CI/CD pipeline run?

A The pipeline can fail to alert the team

B The pipeline ignores it and continues

C The infrastructure is deleted

D The code is automatically changed

Failing the pipeline on drift detection alerts the team to fix the mismatch before deployment.

Which of these is NOT a cause of drift?

A Manual changes made directly in the cloud console

B Configuration files left unchanged

C External scripts modifying resources

D Infrastructure as code updates

Unchanged configuration files do not cause drift; drift happens when actual state differs from code.

What is a simple way to fix drift once detected?

A Ignore the drift and continue

B Delete all resources manually

C Run <code>terraform apply</code> to align infrastructure with code

D Restart the CI/CD server

Applying the Terraform configuration updates the infrastructure to match the code, fixing drift.

Explain what drift detection is and why it matters in a Terraform CI/CD pipeline.

Think about how code and real infrastructure can get out of sync.

Describe how you would automate drift detection in a CI/CD pipeline using Terraform commands.

Consider what commands show differences and how the pipeline should respond.