Pod Management & Scheduling Flashcards

Which scheduler priority mechanism allows critical system pods to preempt lower-priority pods when resources are scarce?

Answer: PriorityClass

A PriorityClass assigns a numeric priority to pods; higher-priority pods can preempt (evict) lower-priority pods to get scheduled.

What does `kubectl rollout restart deployment/myapp` do?

Answer: Triggers a rolling restart of all pods in the Deployment without changing the spec

`rollout restart` updates a pod template annotation to trigger a rolling update, cycling all pods while maintaining availability.

Which Pod volume type mounts a directory from the host node's filesystem directly into the pod?

Answer: hostPath

A `hostPath` volume mounts a specific path from the underlying node into the pod, giving direct access to host files.

A container's `resources.requests` value affects scheduling how?

Answer: The scheduler only places the pod on nodes with at least that much allocatable resource available

Requests are what the scheduler uses to fit pods onto nodes; a node must have sufficient allocatable capacity to satisfy the pod's requests.

Which field allows you to configure the scheduler to wait before evicting a pod that fails its `NoExecute` taint toleration?

Answer: tolerationSeconds in the toleration spec

`tolerationSeconds` on a `NoExecute` toleration sets how long the pod can remain on a tainted node before being evicted.

What is the function of an admission controller in the context of pod scheduling?

Answer: Intercepts API requests to validate or mutate pod specs before they are persisted

Admission controllers run after authentication/authorization and can reject or modify pod creation requests before the object is stored in etcd.

Which command shows the resource requests and limits currently set on all containers in a running pod?

Answer: Both A and C show this information

Both `kubectl describe pod` (in the Containers section) and `kubectl get pod -o yaml` (under resources) display requests and limits.