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1. What is Kubernetes? Yet another breakthrough discovery from Google came on behalf of Kubernetes following more than 10 years of Google's experience in containerized applications. In short, Kubernetes is an open source platform solution provided by Google to manage a container cluster. Kubernetes has the ability to schedule and execute application containers on a cluster of physical or virtual machines. In application management, the concepts of "labels" and "pods" are used to group the containers that make up an application. Currently, it supports Docker for containers. The best part of Kubernetes is its self-healing mechanisms such as automatic restart, reprogramming and replication of containers used to manage the "desired state" requested by the user. When the user sets the required state, Kubernetes ensures that the state is maintained at all times on the cluster. For example, if a server goes down, it brings it back again to maintain the state. Typically, deploying a container application takes a lot of work. For example, imagine an application that has a cluster of containers on multiple hosts. Let's say

2. it has a web level, an application level, and a database level running on different sets of containers. For the application to work properly, it must communicate between the Web tier, the Application level, and the Database level. It's the communication between separate containers. This requires a lot of hard work, including scripting, monitoring, and container management. But, with Kubernetes, the problem is solved because it does all the hard work for the user. KUBERNETES TERMINOLOGY POD A pod is a unique planning unit in Kubernetes that represents a group of collocated containers. It can not span machines, so all containers in a pod must be scheduled on the same host and can be deployed and scaled as a single application. Each pod has a unique IP address and pod containers use a shared network namespace. REPLICATION CONTROLLER A pod is not able to handle a failure situation. In a situation such as a crash in the node, where the pod is running, the pod is removed from the cluster. But in order to provide the desired state to the user, we must ensure that the state is maintained. The replication controller monitors the cluster and ensures that a given number of pods are running at all times. If there are more specified, it will kill some, if there are too few, it will create some. For a pod to be monitored by a replication controller, we must set the pod as a template inside the replication controller.

3. Service - the base unit that acts as a load balancer for other containers. Label - a key / value pair assigned to a resource to identify a set of related resources Selector - an expression that supports to match the user-defined labels KUBERNETES ARCHITECTURE The basic Kubernetes architecture contains nodes and master. KUBERNETES MASTER There are three important parts of the master are as follows; 1. API Server - manages the tasks of all master and node components via API calls 2. Etcd - stores and replicates the current configuration and the state of execution of the cluster 3. Scheduler and Controller Manager - responsible for container planning

4. KUBERNETES NODES A node Kubernetes has the following important processes: 1. Kubelet - responds to the master's commands to manage pods and their containers 2. Proxy - a simple network proxy, which separates the IP address of a target container from the service name For More Information about Docker&Kubernetes ClickHere Ph No: +91-9676446666, E-Mail ID:devopshelpdesk1@gmail.com