[Cloud] Kubernetes Overview

1. Kubernetes

1.1. Overview

Kubernetes is an open-source system that allows organizations to deploy and manage containerized applications like platforms as a service (PaaS), batch processing workers, and microservices in the cloud at scale.

Through an abstraction layer created on top of a group of hosts, development teams can let Kubernetes manage a host of functions--including load balancing, monitoring and controlling resource consumption by team or application, limiting resource consumption and leveraging additional resources from new hosts added to a cluster, and other workflows.


1.2. Kubernetes Architecture (Master, Worker) 

The Kubernetes master is responsible for maintaining the desired state for your cluster. The master can also be replicated for availability and redundancy. When you interact with Kubernetes, eg. via the kubectl command-line interface, you’re communicating with the master.

The worker nodes in a cluster are the machines (VMs, physical servers, etc) that run your applications and cloud workflows. The master controls each node; you’ll rarely interact with nodes directly.


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