Kubernetes components work together to ensure the availability and proper functioning of resources

like ReplicaSets. Let’s analyze each option:

A . kube-proxy

Incorrect: The kube-proxy manages network communication for services and pods by implementing

load balancing and routing rules. It does not guarantee the availability of ReplicaSet pods.

B . kube-scheduler

Incorrect: The kube-scheduler is responsible for assigning pods to nodes based on resource

availability and other constraints. While it plays a role in pod placement, it does not ensure the

availability of ReplicaSet pods.

C . kube controller

Correct: The kube controller (specifically the ReplicaSet controller) ensures that the desired number

of pods specified in a ReplicaSet are running at all times. If a pod crashes or is deleted, the controller

creates a new one to maintain the desired state.

D . kubelet

Incorrect: The kubelet ensures that containers are running as expected on a node but does not

manage the overall availability of ReplicaSet pods across the cluster.

Why Kube Controller?

ReplicaSet Management: The ReplicaSet controller within the kube controller manager ensures that

the specified number of pod replicas are always available.

Self-Healing: If a pod fails or is deleted, the controller automatically creates a new pod to maintain

the desired state.

JNCIA Cloud Reference:

The JNCIA-Cloud certification covers Kubernetes control plane components, including the kube

controller. Understanding the role of the kube controller is essential for managing the availability and

scalability of Kubernetes resources.

For example, Juniper Contrail integrates with Kubernetes to provide advanced networking and

security features, relying on the kube controller to maintain the desired state of ReplicaSets.

Reference:

Kubernetes Documentation: ReplicaSet Controller

Juniper JNCIA-Cloud Study Guide: Kubernetes Control Plane