KCNA Kubernetes Architecture & Components 5

Question 1

What is the Container Runtime Interface (CRI) in Kubernetes?

Accepted Answer

A plugin API that allows kubelet to use different container runtimes without recompilation

Answer

CRI is a plugin interface that enables kubelet to work with different container runtimes (like containerd or CRI-O) through a standard gRPC API.

Question 2

Which Kubernetes object is used to expose a group of Pods as a network service with load balancing?

Accepted Answer

Service

Answer

A Service provides a stable virtual IP and DNS name for a set of Pods, load-balancing traffic across healthy Pod endpoints.

Question 3

What does the term 'reconciliation loop' mean in the context of Kubernetes controllers?

Accepted Answer

Continuously comparing actual cluster state to desired state and making corrections

Answer

A reconciliation loop watches for changes and continuously drives the actual state of the cluster toward the declared desired state.

Question 4

Which field in a Pod spec lets you specify that a Pod requires a node with a particular label?

Accepted Answer

nodeSelector

Answer

nodeSelector is the simplest node selection constraint; it restricts scheduling to nodes that have all the specified key-value label pairs.

Question 5

What is a Kubernetes Taint used for?

Accepted Answer

Repelling Pods from a node unless the Pod has a matching Toleration

Answer

Taints allow nodes to repel a set of Pods; only Pods with matching Tolerations can be scheduled onto a tainted node.

(KCNA) Kubernetes and Cloud Native Associate Practice Test