Kubernetes Informational

What is a Kubernetes?
Kubernetes is an open-source distributed system that abstracts the underlying physical infrastructure, making it easier to run containerized applications at scale. A containerized application is defined as a fully packaged and portable computing environment. An application, managed through the entirety of its life cycle by Kubernetes, is composed of containers gathered as a set and coordinated into a single unit. An efficient cluster manager layer lets Kubernetes effectively decouple this application from its supporting infrastructure.
For a much simpler definition of what Kubernetes is, Kimoon Kim, a senior architect at Pepperdata, claims that “Kubernetes is a software that manages many server computers and runs a large number of programs across those computers. On Kubernetes, all programs run in containers so that they can be isolated from each other, and be easy to develop and deploy.” Essentially, Kubernetes makes it easier to configure, deploy, manage, and monitor even the largest-scale containerized applications. It also aids IT professionals in managing container and associated application lifecycles, as well as problems such as high availability and load balancing.

What can Kubernetes do for you?

With modern web services, users expect applications to be available 24/7, and developers expect to deploy new versions of those applications several times a day. Containerization helps package software to serve these goals, enabling applications to be released and updated without downtime. Kubernetes helps you make sure those containerized applications run where and when you want and helps them manage the resources and tools they need to work.

Understanding How Kubernetes Works

To understand the process of how Kubernetes works, we must first understand some basic terms like Pod, Cluster, and Node. Kubernetes is architected as a cluster of Nodes. Containers are deployed into Pods using the Control Plane. The Control Plane manages the Nodes and the Pods. Below is a guide to better understand this process:

• What is a Container?
  Kubernetes.io defines a Container as: “A container image is a ready-to-run software package, containing everything needed to run an application: the code and any runtime it requires, application and system libraries, and default values for any essential settings”
• What is a Pod?
  A Pod represents a group of one or more Containers running together on a Cluster. Normally a Pod will have a single type of application or it can have multiple applications if they are closely related. Each Pod is assigned a unique IP address within the Cluster, that enables the application to use ports without conflict. 
• What is a Node?
  Nodes are composed of physical or virtual machines on a Cluster; these “worker” machines have everything necessary to run application Containers, including the Container runtime and other critical services. 
• What is a Master?
  A master Node is a Node that controls and manages a set of worker Nodes and resembles a Cluster in Kubernetes.
• What is a Cluster?
  A Cluster is a group or bunch of Nodes that run your containerized applications. You manage the Cluster and everything it includes – in other words, you manage each application(s) – with Kubernetes.

Why is Kubernetes important?

• It has become the industry standard for deploying containers in production
  We have now reached the point that the industry has generally standardized Kubernetes. The consensus among all the different vendors is that the technology is stable, multi-dimensional and that people can feel comfortable when they are making technology investments and architectural decisions. Organizations can feel confident in choosing Kubernetes for deploying containers in production.
• It is the next big trend for managing virtualized infrastructure
  If you are thinking about what are the next three to five years of my career going to look like and what technology should you focus on, Containers are where you’re going to see the most innovation and opportunity to be part of the transformation helping the business become more agile.
• Developers love it
  Containerization has solved a big problem for system developers. It allows a seamless transition of applications from development environments to production environments. Without Containers, developers sometimes find that applications do not run the same way in production as they did on the developers’ systems. Kubernetes makes it easier for them to package the applications and all the dependencies that go with their application and deliver a consistent solution across development and production environments
• It can run any containerized application
  Enterprise architects are always balancing the need to make their legacy applications cost-effective and the need to support future innovation. In the past, the tools necessary to support those needs were very different. Kubernetes is an interesting technology in that it is proven with customers in production that you can not only use it to build new, cloud-native microservice applications, but people have also been able to migrate existing applications into Containers and run them in Kubernetes.  

Sources:
Kim, K. (2020, December 08). Why Kubernetes is winning in the enterprise. Retrieved April 09, 2021, from https://www.pepperdata.com/blog/why-kubernetes-and-container-orchestration-is-winning-in-the-enterprise/

What is Kubernetes? (n.d.). Retrieved April 09, 2021, from https://www.redhat.com/en/topics/containers/what-is-kubernetes

What is Kubernetes? (2021, February 01). Retrieved April 09, 2021, from https://kubernetes.io/docs/concepts/overview/what-is-kubernetes/

About the Author
Mohamed Abarra is a Senior Systems Engineer who joined Altron Inc. in 2020. His extensive and impressive resume includes over 20+ years of system engineering work at places such as SRI, IBM, and Verizon. Furthermore, Mohamed has extensive experience specializing in infrastructure, virtualization, cloud, and vulnerability management to go along with his in-depth knowledge of Linux, Solaris, Windows, VMware, AWS, Azure, and Hardware architecture. His expertise and positive attitude have been a great addition to our Altron family!