🃏 CI/CD Pipelines Flashcards

Q: What are the CodeDeploy deployment types for EC2?

A: In-place (stop app, update, restart) and Blue/Green (new instances, traffic shift, terminate old). Blue/green requires an ELB.

Q: How does CodePipeline handle cross-account deployments?

A: The pipeline assumes an IAM role in the target account. Artifacts are encrypted with a CMK shared across accounts via key policy grants.

Q: What is a CodeDeploy deployment group?

A: A set of target instances/tasks identified by tags, ASG, or ECS service. Each group has its own deployment configuration and alarm settings.

Q: What are CodeDeploy lifecycle hooks for EC2?

A: ApplicationStop → BeforeInstall → AfterInstall → ApplicationStart → ValidateService. BeforeBlockTraffic and AfterBlockTraffic for ELB.

Q: How do you implement manual approval in CodePipeline?

A: Add a Manual Approval action in a stage. Optionally send SNS notification. Pipeline pauses until approved/rejected or times out (7 days max).

Q: What is CodeBuild batch build?

A: Run multiple build jobs in parallel from a single buildspec. Useful for testing across multiple runtimes or running unit/integration tests simultaneously.

Q: What is CodeDeploy canary deployment for Lambda?

A: Shifts a percentage of traffic (e.g., 10%) to new version, waits, then shifts remaining 100%. Rolls back if alarms trigger during the wait period.

Q: How do you trigger a pipeline from a Git push?

A: EventBridge rule detects CodeCommit/GitHub push events and starts the pipeline. Preferred over polling for lower latency and cost.

Q: What happens when a CodeDeploy deployment fails?

A: If auto-rollback is enabled, CodeDeploy redeploys the last known good revision. For blue/green, it reroutes traffic back to the original instances.

Q: What is a CodePipeline artifact?

A: A ZIP file stored in the pipeline S3 bucket containing source code, build output, or deployment packages passed between stages.