Kubernetes: what it is, importance and advantages of using it

For those immersed in the world of application and software development, the word “ Kubernetes ”, although strange, is not new. It is a container management system, solutions that virtualize OSs in a microservices architecture.

To make use of containers without them multiplying at high speed, one solution is to use Kubernetes. This is because the tool provides the orchestration and management that are needed to deploy containers at scale for large workloads.

In practice, Kubernetes, as well as containers and microservices converge on one purpose: establishing an ecosystem of solutions that simplify the programmer ‘s life ‘s life .

But this is just a definition of Kubernetes — for anyone entering the field or seeking new knowledge, it is essential to understand the subject in depth.

In other words, from the concept to its practical application in the day-to-day life of a development company. After all, what are the advantages of Kubernetes and why is it so popular today?

Understand more about what Kubernetes is and the main benefits of using this tool.

What is Kubernetes and how does it work?

Kubernetes is an open source system system for orchestrating and cluster management for container-based applications.

According to the official website, kubernetes.io , the definition for the system is as follows:

“ Kubernetes is an open source system for automating the deployment, scaling, and management of containerized applications. It groups the containers that make up an application into logical units for easy management and discovery. Kubernetes builds on 15 years of experience running production workloads at Google, combined with best ideas and practices from the community. “

The mention of Google makes sense, as Kubernetes was created by the company, which after some time made it an open source platform, allowing everyone to use it.

What does all this mean, in practice, in a simple to understand way?

Let’s go: nowadays, users of applications and software — the vast majority of which are SaaS, which are hosted in the cloud — expect complete and uninterrupted functionality.

However, today, the need for developers to update applications and software is also greater than it was years ago.

As you know, to update an application, you need to mobilize it completely.

In the past it was like this: you needed to download the update or install it directly from a CD, which forced the company to face a certain period of downtime.

With containers, which we will explain below, it is possible to “package” the application, so that the company isolates different parts of the software and works on them freely and quickly, without compromising the stability and functionality of the application. as a whole.

And what about Kubernetes in all this dynamics? It is the container management system, which helps control resource allocation and traffic management for cloud applications as well as microservices.

It also helps simplify various aspects of service-oriented infrastructures.

Kubernetes allows the programmer to guarantee exactly where and when container-based applications will run, as well as helping to find the right resources and tools to work with.

Containers

Before understanding more about Kubernetes, it is important to know what Linux containers are and their function. They can be defined as a set of one or more processes organized separately from the system.

They can be portable and consistent throughout the migration between development, testing and production environments. It is important to know that the container is different from the virtualization process, which involves creating a virtual version of something.

Having understood this, we can say that Kubernetes is an open source platform that automates the operations of Linux containers.

With this, it is possible to eliminate most of the manual processes for implementing and scaling containerized applications. This platform is ideal for hosting cloud-native applications.

This tool allows both physical and virtual elements to communicate in a clear and transparent way. Therefore, each of these groups of physical and virtual elements is called a cluster.

Clusters can communicate through a network developed by the tool for this purpose. See the mechanisms that are part of Kubernetes:

• Master: this is the center of everything. This is where the API and the most essential components that manage the cluster that runs the containers run;
• Nodes: are virtual or physical machines that capture instructions from the Master and then process access to applications;
• Pod: pods are the smallest unit of this tool and are where the containers run;
• Deployments: help control and organize the deployment of Pods. They may contain information about the environment, volume mapping and tags;
• Services: this is where the executed Pods are organized using tags;
• Kubelet: is a service running on nodes that reads container manifests, in addition to ensuring that they have been started and are running,
• Kubectl: This is the Kubernetes command-line configuration tool.

Cloud-native

Kubernetes has a great advantage, which is that it can group clusters on public, private or hybrid cloud hosts. That’s why it’s so widely used to host cloud-native applications.

But what is a cloud-native application? This is any application designed to take full advantage of cloud platforms. Thus, these applications can:

• Scale horizontally;
• Use cloud platform services;
• Automatically scale with proactive and reactive actions;
• Enables non-blocking asynchronous communication in a loosely coupled architecture.

Still related to cloud-native applications is the “Twelve Factor” application, a set of standards for developing applications that are delivered as a service.

Furthermore, cloud-native applications avoid what is called “monolithic architecture”, in which all layers of the software are unified.

Therefore, making updates and changes to these systems is a huge challenge, as a single change can force the entire team to rewrite the source code, which also slows down the testing phase.

A microservices architecture changes this panorama, as it breaks down applications into individual, minimal and independent components.

Each component represents a microservice, which allows companies to isolate these layers and work autonomously on top of them, without affecting the overall performance of the application.

What is Kubernetes Deployment?

As we explained, Kubernetes Deployment is a common workload that can be created and managed directly.

It is one of the elements of the Kubernetes architecture, considered an “Object” with several functionalities that automate several processes during the development of an application.

Kubernetes Deployment is used to tell Kubernetes how to create or modify certain instances of containerized application pods.

This Deployment can scale the number of replica pods, as well as allow the distribution of updated code in a controlled manner or rollback to a previous version of the application.

It’s basically what makes it possible — whether manually or automated — for changes to be made to containerized applications.

As? Well, Kubernetes Deployment is the process of providing declarative updates to pods and ReplicaSets.

Emphasizing: ReplicaSets are replication sets, an interaction in the design of the replication controller (Replication Controllers) with flexibility in how the controller recognizes the pods it must manage.

It replaces replication controllers due to its greater replication selection capability.

In other words, going back, Deployment allows users to write exactly what state they want in the manifest file (called YAML), and the Deployment controller will change the current state to the desired one.

When and how did Kubernetes emerge?

It is often said that Kubernetes dates back to the beginning of the last decade, more specifically 2014. This is a correct definition, but the platform’s roots date back to 2003, with the creation of the Borg System by Google.

This was a small Google project — at that time, still a growing company. Borg’s intention was to create a new version of the Google search engine.

In practice, Borg was a large-scale internal cluster management system that ran hundreds of thousands of workloads, from countless different applications, and across many clusters, each with up to tens of thousands of machines.

In 2013, a decade later, Google evolved Borg into the Omega cluster management system: a flexible, scalable scheduler for large computing clusters.

In 2014, Google introduced Kubernetes as we know it today — in practice, a version of Borg that was open source.

Later this year, companies such as Microsoft, Red Hat, IBM and Docker joined the Kubernetes community.

What is Kubernetes for?

Kubernetes is an open source system that helps your company deploy, scale, and manage container-based applications.

It is an enabling system that helps simplify various aspects of service-oriented infrastructures.

It helps automate various operational tasks of container management, with built-in commands for application deployment.

This way, it is possible:

• Deploy apps anywhere : Enables you to run apps in on-premises deployments, in public clouds, and in hybrid environments.
• Execute services more effectively : gives you greater control, making your team’s actions more efficient. For example, Kubernetes allows you to automatically adjust the size of a cluster to run a particular service.
• Increase development speed : Create applications based on cloud-native microservices as well as support containerization of existing applications.

Why is Kubernetes important?

At a high level, it’s easy to see the importance of Kubernetes for organizations. As we mentioned, Kubernetes is an open source orchestrator, completely flexible and scalable, capable of completely facilitating container management.

Among its main benefits, we can list:

Portability and flexibility

Kubernetes works with virtually any container launch type.

Additionally, Kubernetes can work with virtually any type of infrastructure (public cloud, private cloud, or an on-premises server) as long as the host OS is Linux or Windows (from a 2016 version or newer).

What about portability? Well, Kubernetes is highly portable and can be applied in different environments, with different configurations.

Multi-cloud

Due in part to its portability, Kubernetes can host workloads running on a single cloud or even spread across multiple clouds.

In other words, we are talking about a solution that facilitates the scaling of the application environment.

It is worth saying that there are other cluster orchestrators on the market, but only Kubernetes goes further, allowing the company to adapt to a multi-cloud and hybrid strategy.

Provides greater productivity to the developer

With Kubernetes, development teams can scale and deploy faster than ever before.

Instead of deploying once a month — often in critical, high-stress situations — teams can now deploy multiple times a day.

Open source

The fact that Kubernetes is open source is also a benefit, as it allows it to be used and modified by all interested parties.

In practice, Kubernetes has several corporate sponsors, but none of them control the platform.

Market leader

Kubernetes adoption is increasingly increasing. According to data released by Container Journal , 59% of companies interviewed said they were running Kubernetes in production.

Why is this an advantage? Well, the more developers and engineers know about Kubernetes, the more knowledge spreads around the world — and more easily.

It is something that reduces the learning curve for companies that adopt it. Additionally, Kubernetes has a large ecosystem of complementary software projects and tools that make it easy to extend its functionality.

Kubernetes organization

The components of a cluster generally assume one of two possible roles: they can be the master or the node. The components that assume the role of server are responsible for establishing communication with other clusters.

On the other hand, node components carry out the work assigned by the applications that run on them. Kubernetes Linux manages node elements through containers.

The master passes instructions to be executed to the nodes within each cluster. Nodes can create and delete containers to fulfill these instructions. These creation and elimination processes are parameterized by scalability rules.

A pod is a Kubernetes work unit made up of containers that work within the same node. They even share resources with each other. We also have volumes, which are basically containers for persisting information temporarily or definitively.