Scheduling and Scaling Flashcards

Which field in a Pod spec allows you to specify a custom scheduler instead of the default one?

Answer: schedulerName

The `schedulerName` field in a Pod's spec tells Kubernetes which scheduler should bind the pod to a node.

A node has the taint `env=prod:NoExecute`. Which toleration allows an existing pod to remain on that node?

Answer: key: env, operator: Equal, value: prod, effect: NoExecute

A NoExecute toleration must match the taint's key, value, and effect exactly to prevent eviction of an already-running pod.

What does the `minAvailable` field in a PodDisruptionBudget specify?

Answer: The minimum number of pods that must remain available during a voluntary disruption

`minAvailable` defines how many pods (absolute or percentage) must stay running when voluntary disruptions occur.

A VerticalPodAutoscaler in 'Off' mode does which of the following?

Answer: Computes recommendations without applying them

'Off' mode causes VPA to calculate and expose resource recommendations without modifying any pods.

Which Kubernetes object defines the relative priority of pods when the scheduler must preempt lower-priority pods?

Answer: PriorityClass

A PriorityClass assigns an integer priority value to pods; the scheduler uses this to determine which pods to preempt when resources are scarce.

A Horizontal Pod Autoscaler targets 50% CPU utilization. Current utilization is 80% across 4 pods. How many replicas will HPA target?

Answer: 7

HPA calculates ceil(4 × (80/50)) = ceil(6.4) = 7 replicas to bring utilization to the target.

Which field in a Pod spec directly pins the pod to a specific node by name, bypassing the scheduler entirely?

Answer: nodeName

Setting `nodeName` skips scheduling altogether and forces the pod onto the named node.