API Server – provides all the operation on cluster using the API. Control Manager – regulates the state of cluster and performs a task. Cluster Store – stores the configuration information which can be used by each of the nodes Scheduler – distributes the workload.

The Kubernetes master runs the Scheduler, Controller Manager, API Server and etcd components and is responsible for managing the Kubernetes cluster. Etcd Etcd is a distributed, consistent key-value store used for configuration management, service discovery, and coordinating distributed work. API Server When you interact with your Kubernetes cluster using the kubectl command-line interface, we are actually communicating with the master API Server component. Scheduler The Scheduler watches for unscheduled pods and binds them to nodes via the /binding pod subresource API, according to

Kubernetes master is the in charge of the cluster. Kuberenetes master should be of linux 64 based. The K8’s master have 4 components. They are1. api-server- Server of API’s. It contains all the APIs provided by K8s. It act as the front-end to the control panel, we access via REST API. Similar to ears in human body, it receive the requests2. cluster store – All the requests / data stored in cluster store. etcd is the storage unit use by

It is the smallest unit in kubernetes world Pod contain a self sufficient unit, like network It has a life cycle- pending, running , succeded/failed

docker – which builds and run the container. kubelet – A service for communication with etcd etc. kube-proxy – it is resposible for managing network. it makes the ports available to external.

API Server : The apis to communicate with outside world and between components. It provides api for all the operationsetcd : it is a data store used by Kubernetes to store the config data. All the communication to etcd is via api server Controller Manager: It runs in a loop to check teh state of each node Scheduler: this is the service which manages teh workload of nodes

1.Kubelet Responsible for instantiates the pod. and communicates with master. 2.Kube-proxy Responsible for network management 3.pod pod is a logical entity which contains one or more containers 4.container Where the application is running

Managing contianers Automatic Scalling Up or down Maintain pods Configuration done by Yaml or Json Manage Mulitple Contianers Always maintain desired Containers Automatic creations of failed contianers

kube-apiserver ( Ear ) Need to interact with your Kubernetes cluster? Talk to the API. The Kubernetes API is the front end of the Kubernetes control plane, handling internal and external requests. The API server determines if a request is valid and, if it is, processes it. You can access the API through REST calls, through the kubectl command-line interface, or through other command-line tools such as kubeadm. kube-scheduler Control plane component that watches for newly created Pods with no assigned node, and selects a

A Kubernetes cluster consists of a set of worker machines, called nodes, that run containerized applications. Every cluster has at least one worker node.he worker node(s) host the Pods that are the components of the application workload. The control plane manages the worker nodes and the Pods in the cluster. kubelet An agent that runs on each node in the cluster. It makes sure that containers are running in a Pod.The kubelet takes a set of PodSpecs that are provided through various mechanisms and ensures that the containers described in

a) kube-apiserver Server of Api’s Front end to the Master Node Any request from Inside or outside the kubernetes is received by API server Exposes the REST API Consumes JSON (via manifest file) b) Cluser store Persist storage for cluster state and config Uses etcd to manage c) Kube-Controller-Manager Manager/Controller of Controllers such as Node Controller, Endpoint controller, Namespace controller etc Watches the changes in API Server Helps maintain the desired state d) Kube-scheduler Watches apiserver for new pods Schedule

etcd – It is the storage. it is key value pair. apiserver – It is the listener scheduler – it schedules, mean add new pods if necessary. controller manager – it monitors the pods always.

Tool for container orchestration – can manage multiple containers running on different nodes; it was created by Google and later made open source. It has a master which “manages” the several worker nodes which contain pods where the application is run. 2. Improves productivity through container orchestration and easy installation. hence makes it easy for managing deployment. 3. Faster and Simpler deployment of containerized applications. Hence provides consistency for different environments – QA, Dev, Staging etc – hence a better

There are mainly four components in kubernetes master.They are: Api server: Contains all apis available in k8s.Each api is a feature .Api server accepts input in JSON format Cluster store : Cluster store is the source of truth of a master.All requested datas are store in cluster store.It uses etcd Controller -Controller watches for changes in worker nodes. Kube scheduler -Assigns pods to nodes

kube-api-server The API server is the front end for the kube master etcd – act as cluster data storage Scheduler assign tasks to the worker node controller manager manages the desire number of pods and notifies if something goes down

Which contain the kubelet- which registers the pod to the kubernetes master Container engine-which pull docker from registry

Kubernetes – Master Machine Components API Server Kubernetes is an API server which provides all the operation on cluster using the API.  Controller Manager This component is responsible for most of the collectors that regulates the state of cluster and performs a task and is responsible for collecting and sending information to API server. Scheduler This is one of the key components of Kubernetes master. It is a service in master responsible for distributing the workload. It is responsible for

1) Allow us to run or manage multiple containers. 2) Whenever there’s a issue, the kubernetes will self heal itself. 3) Improve the stability of the application. 4) Reduced size as Kubernetes don’t have OS. 5) Cost cutting. 6) Multiple computing services can be managed from the single dashboard.