Working cycle of Kubernetes and its components

The working cycle of Kubernetes and its components involves the following steps:

  1. A user or application submits a request to the Kubernetes API server to create or modify a resource (e.g. a pod, a service, a deployment).
  2. The API server validates the request and stores it in etcd, the distributed key-value store that stores the configuration data of the cluster.
  3. The kube-controller-manager watches the etcd store for changes and updates the state of the cluster to reflect the desired state.
  4. The kube-scheduler receives a notification from the API server about a new pod that needs to be scheduled. It uses a scheduling algorithm to determine the best placement for the pod based on resource availability and constraints.
  5. The kube-scheduler sends a command to the API server to create the pod on the chosen worker node.
  6. The kubelet on the worker node receives the command and pulls the required container images from the container registry. It then starts the containers and runs them in a container runtime (e.g. Docker, containerd).
  7. The kubelet communicates with the master nodes to report the status of the pods and the node, and to receive updates and commands.
  8. If the state of the cluster or the resources in the cluster changes (e.g. due to a scale-up or scale-down event, a failure, or a rolling update), the kube-controller-manager and the kube-scheduler work together to ensure that the desired state is reflected in the actual state.

This is a general overview of the working cycle of Kubernetes and its components. The specific steps and interactions may vary depending on the specific resources and actions being performed and the configuration

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