Kubernetes basic Concepts

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This basic concepts helps you to obtain deeper understanding of how kubernetes works. To get better understanding need knowledge of kubernetes API. Kubernetes APIS help to understand the below thing of cluster desired state like,

  • what applications or other workloads you want to run
  • what container images they use
  • the number of replicas
  • what network and disk resources you want to make available
This thing achieved by creating kubernetes object using the kubernetes APIS. Object creation is achieved by using the command line interface kubectl.

Once we set desired state, the Kubernetes Control Plane makes the cluster's current state match the desired state via the Pod Life-cycle Event Generator. Kubernetes perform variety of task in Pod Life-cycle generation. Pod Life-cycle Event generation contains tasks.
  • Starting and restarting the containers
  • Scaling the number of given replicas
Kubernetes consists of collection of process running on cluster.

Kubernetes master run three process into a single node. Those processes are kube-apiserver, kube-controller-manager and kube-scheduler. Typically all these processes run on a single node in the cluster, and this node is also referred to as the master.The Kubernetes master is responsible for maintaining the desired state for your cluster. The master can also be replicated for availability and redundancy.

Each non-master node in cluster has two processes. Those processes are kubelet and kube-proxy. This nodes in a cluster are the machines that run your applications and cloud workflows. The Kubernetes master controls each node; you’ll rarely interact with nodes directly.
Kubernetes MasterNode Process

Kubernetes Non-Matser Node Process






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