KCNA - Cloud Native Application Delivery (16% of the exam) - Section 3.3
Compare deployment strategies and select one for a stated risk requirement.
Recreate, rolling update, blue-green and canary, plus progressive delivery with automated analysis. Candidates should reason about downtime, rollback speed and blast radius rather than recite definitions.
rolling updateblue-green deploymentcanary deploymentprogressive deliveryArgo Rollouts
A team wants canary and blue-green releases with automated metric analysis on Kubernetes, going beyond what the built-in Deployment object offers, and is evaluating Argo Rollouts. Which statement about Argo Rollouts is correct?
AIt is a scheduling add-on that replaces the default Kubernetes scheduler to place Pods for advanced releases.
BIt ships inside Kubernetes core as part of the Deployment object, so no extra controller is required to use it.
CIt is a controller that only automates the recreate strategy and cannot perform canary or blue-green traffic shifting.
DIt is a controller from the CNCF graduated Argo project that adds a Rollout resource for canary and blue-green releases.check_circle Correct
Argo Rollouts, part of the CNCF graduated Argo project, adds a Rollout resource for canary and blue-green releases with automated analysis. Argo Rollouts is an installable controller that introduces the Rollout custom resource, extending Kubernetes with progressive strategies and metric-based analysis the built-in Deployment lacks.
Why A is wrong: This is tempting because releases involve Pod placement, but Argo Rollouts is a deployment controller and does not replace the Kubernetes scheduler.
Why B is wrong: This is plausible because it resembles a Deployment, but Argo Rollouts is a separate controller you install, not part of Kubernetes core.
Why C is wrong: This is tempting if one assumes limited scope, but Argo Rollouts exists precisely to provide canary and blue-green traffic shifting beyond the built-in strategies.
Why D is correct: This is correct because Argo Rollouts is part of the graduated Argo project and provides a Rollout custom resource enabling advanced strategies with automated analysis.
Answers that look right on this material and are not. Each one is a distractor from a different question in the KCNA bank for this domain.
The HorizontalPodAutoscaler
errorWhy it is wrong: Tempting because it also reacts to metrics, but it adjusts the replica count in response to load and has no concept of release versions, traffic steps, or promotion gating, so it cannot orchestrate a canary.
Continuous integration, the practice of frequently merging and automatically building and testing code changes.
errorWhy it is wrong: This is tempting because it is a core cloud native practice, but it concerns merging and testing code, not staged, metric-gated traffic shifting to a release.
Continuous integration
errorWhy it is wrong: Tempting because it is a core delivery-pipeline term, but it covers merging and building code with automated tests before release, not the gradual metric-gated rollout of a running release.