KCNA Scheduling and Scaling 3

Question 1

What is the purpose of the `topologySpreadConstraints` field in a Pod spec?

Accepted Answer

To distribute pods evenly across failure domains such as zones or nodes

Answer

`topologySpreadConstraints` lets you control how pods are spread across topology domains to improve availability and balance.

Question 2

Which HPA metric type allows scaling based on a metric exposed by an external system outside the cluster?

Accepted Answer

External

Answer

The `External` metric type in HPA enables scaling based on metrics from systems outside the Kubernetes cluster, such as a cloud queue depth.

Question 3

A pod with `requiredDuringSchedulingIgnoredDuringExecution` node affinity cannot be scheduled if the rule is not satisfied. What happens to the pod?

Accepted Answer

It stays Pending until a matching node becomes available

Answer

Hard affinity rules (`required...`) cause the pod to remain Pending indefinitely if no node satisfies the constraint.

Question 4

What does the Cluster Autoscaler do when a node has been underutilized for the scale-down delay period?

Accepted Answer

Terminates the node and reschedules its pods elsewhere

Answer

Cluster Autoscaler removes underutilized nodes from the node group and reschedules the pods that were running on them.

Question 5

Which kubectl command removes a taint from a node?

Accepted Answer

kubectl taint nodes <node> key=value:Effect-

Answer

Appending a `-` at the end of the taint specification in `kubectl taint nodes` removes that taint from the node.

(KCNA) Kubernetes and Cloud Native Associate Practice Test