What is Kubernetes? | k8s

K8s is commonly known in Java and containers for running containers in the cloud. Kubernetes is also used in web development. Integrated cloud infrastructure combines an onsite infrastructure with a public cloud environment to efficiently manage native applications in the cloud. It distributes application workloads in Kubernetes clusters and simplifies containers network needs automatically. Kubernetes allocates storage and persistent volumes to running containers automatically scaled. Find out what enterprises use Kubernetes for the creation, deployability, or deployment of modern apps.

Introduction

Kubernetes, also known as K8s, is a powerful open-source system initiated by Google and now maintained by the Cloud Native Computing Foundation (CNCF). It's designed to automate, scale, and manage containerized applications, enabling developers to group containers that make up an application into logical units for effortless management and discovery.

Containers vs. Virtual Machines vs. Traditional Infrastructure

Modern-day software development has been revolutionized by containerized applications. Unlike in a traditional environment where applications are installed directly on servers, containers encapsulate applications and their dependencies into a self-contained unit that can run on any operating system.

On the other hand, virtual machines (VMs) offer a different kind of abstraction. A VM is a software emulation of a physical server, complete with an operating system, binary code, and system libraries. Multiple VMs can run on a single physical machine, but they are more resource-intensive than containers.

Compared to traditional infrastructures and VMs, containers stand out due to their lightweight nature and the ability to share the host's operating system. This enables higher efficiency and resource utilization in production environment, making containers the ideal choice for deploying multiple applications on a single physical server.

Kubernetes Defined

At its core, Kubernetes is a full container management and orchestration platform. But what does this really mean? Well, think of Kubernetes as the conductor of a symphony. It ensures that all instruments (containers) play at the right time and in harmony. Kubernetes schedules and automates the deployment, scaling, and management of containerized applications, efficiently utilizing infrastructure resources.

To put it simply, imagine you have a lunchbox full of different items (the containers). Without an organizing system to manage containers, it would be a mess to carry and handle. Kubernetes is like the lunchbox organizer, arranging and managing your items neatly and effectively.

What Kubernetes Does and Why People Use It

Kubernetes is a key component in the cloud native technologies ecosystem, delivering immense value to IT organizations. It manages workloads, ensuring that the system runs efficiently and resiliently. It handles operational tasks deployed containers, like load balancing, scaling, and providing a storage system when required.

In essence, Kubernetes acts as a bridge between physical and cloud platforms and virtual machines, making the management of applications more flexible and scalable. Kubernetes clusters, groups of hosted nodes where containerized applications run, are the backbone of this system. The control plane maintains the desired state of these Kubernetes clusters, ensuring that applications run as expected.

Moreover, Kubernetes enables scaling containerized applications without manual processes involved. This automation eases application development, making Kubernetes an integral part of the continuous integration and continuous deployment (CI/CD) pipeline in many organizations.

Understanding Kubernetes Architecture

The architecture of Kubernetes is designed for scalability and high availability. The fundamental building blocks of container image in Kubernetes are the clusters, each containing one or more containers running in Kubernetes Pods.

Control Plane

The Control Plane, or master node, is the brain of the Kubernetes cluster, responsible for maintaining the desired state. It comprises several components including the API Server, Controller Manager, and Scheduler. The Kubernetes API is the core interface of the Control Plane, facilitating internal communication and serving as container runtime interface and the gateway for external users.

Worker Nodes

These are the machines where applications run. Each node is an individual machine and includes a container runtime, such as Docker, to both manage applications and container operations. Kubernetes nodes also contain a Kubelet, a tiny application that communicates with the Control Plane, and a Kube-proxy, a network proxy reflecting services as defined in the Kubernetes API on each node.

The Kubernetes Pod: Fundamental Unit of a Kubernetes Cluster

In Kubernetes, the smallest and simplest unit is a container images or a Pod. This is a group of one or more containers that are deployed together on the same host. Pods have their own IP addresses and can communicate with other Pods through the Kubernetes Service.

Kubernetes Service and Load Balancing

A Kubernetes Service is an abstract representation of a set of Pods providing the same functionality. It's responsible for enabling network access to a set of Pods, regardless of where they are running. It also handles load balancing across multiple Pods, ensuring the distribution of network traffic to maintain optimal performance.

Kubernetes Volumes: Data Storage in Kubernetes

In the world of Kubernetes, data storage is managed via Volumes. Kubernetes Volumes enable data to persist beyond the lifecycle of an individual container within a Pod, ensuring data is safe even if a container crashes. Kubernetes supports many types of volumes, including local storage, cloud providers' storage services, public clouds like Google Cloud, and network storage systems.

Container Orchestration: Kubernetes vs. Others

Kubernetes isn't the only player in the container orchestration platform market. Other tools like Docker Swarm and Apache Mesos also exist. However, Kubernetes offers a comprehensive feature set, a vibrant open-source community, and compatibility with multiple public cloud providers together, making it the preferred choice for many businesses.

Embracing Kubernetes Native Applications

Kubernetes native applications are designed to leverage the full potential of the Kubernetes environment. They are cloud-native applications that are deployed and managed via Kubernetes, taking full advantage of Kubernetes features such as scaling, load balancing, and service discovery. They follow the principles of the Cloud Native Computing Foundation (CNCF), which fosters the adoption of a new paradigm for building and running applications in a cloud-native manner.

Kubernetes Operators: The Power of Automation

Kubernetes Operators are purpose-built to automate the operational tasks in a Kubernetes environment. They encapsulate human operational knowledge in software to automate complex tasks, reducing manual processes involved. By leveraging the Kubernetes API and Kubernetes resources, operators ensure a desired state, self-heal applications, and perform automatic updates and backups.

Benefits of Kubernetes in Production Environments

Kubernetes offers numerous benefits when it comes to production environments. Deploying applications on Kubernetes ensures high availability, automated rollouts and rollbacks, and efficient resource utilization. By abstracting away the underlying infrastructure, Kubernetes enables applications to run seamlessly across multiple cloud providers or on-premises in data center and centers.

Scalability and High Availability

Kubernetes allows for easy scaling of containerized applications. Kubernetes can automatically adjust the number of running containers based on the traffic pattern and load balance across them. Additionally, Kubernetes ensures that a predetermined number of instances of your applications are running at any given time, thus ensuring high availability.

Continuous Integration/Continuous Deployment (CI/CD) with Kubernetes

Kubernetes facilitates a smooth and efficient CI/CD pipeline, enabling rapid application development and deployment. The features of Kubernetes, such as rolling updates and automatic rollback capabilities, fit naturally into the CI/CD model.

Kubernetes offers an environment where building, testing, and releasing software can happen rapidly, frequently, and more reliably. It can integrate with multiple CI/CD tools, thereby becoming an integral part of the CI/CD process.

The Kubernetes Community and Project

The Kubernetes project is stewarded by the Cloud Native Computing Foundation (CNCF). It is an open-source project, with a vibrant and active community that plays a crucial role in the development and propagation of Kubernetes. The Kubernetes community is diverse and extensive, consisting of contributors, users, and enthusiasts from all over the world, contributing to the codebase, writing documentation, and sharing their experiences.

The Future of Kubernetes and Cloud-Native Development

The future of Kubernetes looks promising. Kubernetes adoption is on the rise as more organizations are looking to harness its power for their cloud-native development. Kubernetes is expected to play a crucial role in driving the transformation towards microservices architectures, containerized applications, and DevOps practices. As the Kubernetes project continues to evolve, so too will the features and capabilities it offers for managing and orchestrating at scale containerized applications and workloads.

Getting Started with Kubernetes

For those looking to get started with Kubernetes, there are numerous resources available. It is recommended to start with the official Kubernetes documentation, which provides comprehensive information on various aspects of Kubernetes. Additionally, the Kubernetes community offers several tutorials and examples to help newcomers.

Here are some practical steps to get started:

1. Understand the basic Kubernetes concepts such as Pods, Nodes, and Services.

2. Set up a local Kubernetes cluster for learning and testing purposes.

3. Deploy a simple application on the cluster.

4. Experiment with Kubernetes features such as scaling and rolling updates.

5. Join the Kubernetes community to learn from others and stay updated.

Conclusion

Kubernetes is a powerful and comprehensive container orchestration platform, designed to automate deploying, scaling, and managing containerized applications. Its extensive feature set, open-source nature, and active community have led to widespread adoption. Whether you are a small business or a large enterprise, Kubernetes has the potential to streamline your operations and propel your cloud-native journey.

With this, we have provided a comprehensive guide on Kubernetes, its benefits, and how to get started with it. Our aim was to arm the readers with enough knowledge to kickstart their journey into the world of Kubernetes and container orchestration.

FAQs

1. Question: What is Kubernetes (K8s)?

Kubernetes, also known as K8s, is an open-source container orchestration platform that automates the deployment, scaling, and management of containerized applications. It provides a highly scalable and flexible infrastructure for running applications in a distributed environment.

2. Question: Why is Kubernetes called K8s?

Kubernetes is often referred to as K8s because the word "Kubernetes" has 11 letters, and the number 8 is used as an abbreviation for the eight letters between "K" and "s". This shorthand notation is commonly used in the tech community to represent lengthy words or terms.

3. Question: What is the basic operational unit of Kubernetes or K8s?

The basic operational unit of Kubernetes or K8s is called a "Pod". A Pod is a group of one or more containers that are deployed together on the same host. It represents the smallest and simplest unit in the Kubernetes architecture and is used to encapsulate and manage containerized applications.

4. Question: How does K8s work?

Kubernetes works by leveraging a distributed architecture that consists of a Control Plane and multiple Worker Nodes. The Control Plane manages the overall cluster state and makes decisions about the desired state of the system, while the Worker Nodes are responsible for running and managing the containers. Kubernetes uses declarative configuration files to define the desired state and automatically reconciles the current state with the desired state.

5. Question: What is Kubernetes used for?

Kubernetes is primarily used for managing and orchestrating containerized applications in a distributed environment. It provides features such as automated scaling, load balancing, service discovery, and self-healing capabilities. Kubernetes enables developers to deploy applications across different environments, including on-premises data centers and public cloud platforms, while ensuring high availability and efficient resource utilization.

6. Question: Should I use Kubernetes or Docker?

Kubernetes and Docker serve different purposes in the container ecosystem. Docker is a platform that allows you to build and package container images, while Kubernetes is a container orchestration platform that manages the deployment and scaling of containers. If you have a single containerized application, Docker may be sufficient. However, if you have complex applications with multiple containers that need to be managed at scale, Kubernetes provides advanced features for orchestration and management.

7. Question: Who built Kubernetes?

Kubernetes was originally developed by a team of engineers at Google, led by Joe Beda, Brendan Burns, and Craig McLuckie. It was later donated to the Cloud Native Computing Foundation (CNCF) in 2015, which now oversees its development and governance as an open-source project.

8. Question: When was Kubernetes released?

Kubernetes was first released as an open-source project in 2014. Since then, it has gained significant popularity and has become the de facto standard for container orchestration in the industry.

9. Question: Where is Kubernetes installed?

Kubernetes can be installed on various platforms, including on-premises data centers, public cloud providers (such as Google Cloud, Amazon Web Services, and Microsoft Azure), and even on local development machines. The installation process may vary depending on the chosen platform, but Kubernetes provides comprehensive documentation and installation guides for each environment.

10. Question: What version of Kubernetes should I use?

The choice of Kubernetes version depends on several factors, including the specific requirements of your applications, compatibility with your infrastructure, and the stability and features offered by different versions. It is recommended to consult the official Kubernetes documentation and the release notes of each version to determine the most suitable version for your deployment. Additionally, it is good practice to stay updated with the latest stable release to benefit from the latest features and security patches.