CKAD Application Deployment Practice Question

Answer analysis

Option-by-option breakdown

For each option: why learners choose it and why it is or isn't the right answer here.

• ✗

  kubectl update deployment nginx --replicas=5

  Why it's wrong here

  The verb 'update' is not a recognized kubectl command; kubectl does not have an 'update' subcommand for modifying resource attributes. Changing a Deployment's replica count requires either the dedicated 'kubectl scale' command or editing the manifest with 'kubectl edit' or 'kubectl patch'. Running 'kubectl update deployment nginx --replicas=5' would immediately fail with an error about an unknown command, so this option cannot set replicas.

• ✓

  kubectl scale deployment nginx --replicas=5

  Why this is correct

  kubectl scale deployment nginx --replicas=5 is the correct command because the scale subcommand directly adjusts the desired replica count for a Deployment, updating spec.replicas in the live object. It also accepts optional flags like --current-replicas to perform optimistic concurrency checks and --timeout to wait for the scale operation to complete. This is the standard imperative way to resize a Deployment's pod count in Kubernetes.

• ✗

  kubectl set scale deployment nginx --replicas=5

  Why it's wrong here

  While 'kubectl set' is a valid verb, it only supports specific subcommands such as 'image', 'env', 'resources', and 'serviceaccount'; 'scale' is not one of them. Combining 'set' with 'scale' creates an invalid subcommand path, and kubectl would reject it as an unknown command. The correct command is simply 'kubectl scale', which is its own top-level verb not a child of 'set'.

• ✗

  kubectl resize deployment nginx --replicas=5

  Why it's wrong here

  The word 'resize' is not part of kubectl's command vocabulary; Kubernetes uses 'scale' to describe changing the number of replicas, not 'resize'. This reflects a common misconception from other container orchestration systems, but kubectl has no 'resize' subcommand for any resource type. Invoking 'kubectl resize deployment nginx --replicas=5' would return an unknown command error, making it impossible to set the replica count.