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Knowledge base Updated: February 5, 2026

What is Kubernetes? A complete guide to managing containers in the cloud

In the modern IT world, containers have revolutionized the way applications are built and deployed. But how do you manage hundreds or thousands of these containers at scale? The answer is Kubernetes. This guide is an in-depth introduction to the de facto standard for container orchestration. Step by

Grzegorz Gnych Grzegorz Gnych

The modern world of software development has been revolutionized by containerization technology, with Docker at the forefront. The ability to “package” an application with all its dependencies into a single, consistent and portable image has solved the historical “but it worked on my computer” problem, becoming the foundation of modern DevOps practices. Running one, five or even ten containers is a relatively simple task. But with the rise in popularity of microservices-based architectures, companies are very quickly facing a new, much more complex challenge - the problem of scale.

How do you effectively manage an environment consisting of hundreds and sometimes thousands of containers, distributed across multiple servers? How to ensure that if one of them fails, it is automatically restarted? How to dynamically scale the application in response to changing workloads? How to ensure reliable communication between all these moving components? Manually managing such an environment is an extremely complicated and error-prone task.

In response to this need, a new category of tools was born, called container orchestrators. After several years of intense competition in this field, one undisputed winner has emerged, which has become a global standard and a kind of “operating system for the cloud.” It is Kubernetes. This guide is a comprehensive introduction to its world, prepared with business and technology leaders in mind, that will explain what this powerful platform is and how to securely and effectively exploit its potential.

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What is Kubernetes and why has it become the standard for container management?

Kubernetes, often shortened to the acronym K8s (because there are eight other letters between the ‘K’ and ‘s’ in the word ‘kubernetes’), is an open-source platform for automating the deployment, scaling and management of applications running in containers. Its main task is orchestration - that is, like a conductor in a large orchestra, ensuring that all containers (musicians) work in harmony, have adequate resources, and that the entire application (symphony) is resilient to failures of its individual components.

The project has extremely solid roots. It was originally developed by Google engineers, who based it on their in-house, battle-tested, massive-scale container management system called Borg. It is on this architecture that global services such as Google’s search engine, Gmail and YouTube have been running for years. In 2014, Google made the strategic decision to release Kubernetes as an open-source project and put it under the care of the newly-formed, neutral Cloud Native Computing Foundation (CNCF).

This move proved to be the key to its global success. The open-source model and the nurturing of an independent foundation have earned Kubernetes tremendous trust and support from the entire technology industry. All major public cloud providers, such as Amazon (AWS), Microsoft (Azure) and Google (GCP), not only fully adopted it, but also created their own managed services based on Kubernetes, further cementing its position as the de facto standard. Today, with its huge, vibrant ecosystem of tools and specialists, Kubernetes is the most mature, flexible and comprehensive platform for managing modern, cloud-based applications.

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What business and technical problems does containerization and orchestration solve?

To fully appreciate the value of Kubernetes, it is necessary to understand what fundamental problems are solved by the technologies on which it is based - containerization and orchestration. Containerization itself, of which Docker has become a symbol, solves the historical problem of consistency and portability of environments. It guarantees that an application packaged in a container will run identically on a developer’s laptop, on a test server and on production, eliminating time-consuming problems caused by differences in configuration.

However, as we begin to deploy multiple containers on a large scale, a new class of problems emerges that orchestration, or Kubernetes, just solves. Among the most important are:

  • High availability and self-repair. Kubernetes constantly monitors the state of the application. If a container running a key microservice crashes, Kubernetes will automatically restart it, often within seconds, without any human intervention. What’s more, if an entire server (cluster node) fails, Kubernetes will automatically move all the applications running on it to other, healthy machines.

  • Scalability and flexibility. Kubernetes allows dynamic adaptation to changing workloads. It can, based on defined metrics (e.g., CPU usage), automatically increase the number of running copies of an application during peak hours and then decrease them at night, optimizing resource consumption and costs.

  • Effective resource management. Kubernetes’ intelligent scheduling mechanism (scheduler) works like an extremely efficient player in Tetris - it arranges containers on available servers in such a way as to “pack” applications as densely as possible and minimize waste of computing power and memory.

  • Simplifying network communication. In a dynamic environment where containers are constantly popping up and disappearing and their IP addresses are changing, Kubernetes provides built-in, reliable service discovery and load balancing mechanisms that fully automate the communication process between application components.

How is Kubernetes different from Docker and how do these technologies work together?

This is one of the most common questions, and the answer is crucial to understanding the entire ecosystem. Docker and Kubernetes are not in competition with each other - they are complementary technologies that operate at different levels of abstraction and work well together.

Docker is primarily a technology for building and running individual containers. Its main task is to create a standard, portable “box” (container image) in which our application and its dependencies are encapsulated. You could say that Docker takes care of what happens inside a single container.

Kubernetes, on the other hand, is a platform for managing and orchestrating multiple containers at scale. Its job is not to build the containers themselves, but to manage their lifecycle across a cluster of servers. It decides where to run a given container, monitors its state, takes care of its scaling and ensures communication between it and the rest of the world.

The following table summarizes this key difference in a simple way:

AspectDockerKubernetesMain objectiveBuilding and running individual containersManagement and orchestration of multiple containersScale of operationsSingle server (host)Multiple servers (cluster)Main functionStandardization and packaging of applicationsAutomation, scaling and lifecycle managementAnalogyStandard shipping containerThe entire container port and fleet of ships

In the most common scenario, developers use Docker to build images of their applications, and then these images are deployed and managed at scale using a Kubernetes cluster.

What are the key benefits of using Kubernetes, such as scalability and high availability?

Implementing Kubernetes as a platform for applications brings a number of powerful benefits to an organization, which translate directly into its agility, resilience and efficiency. Automatic scaling allows resources to be perfectly matched to current demand, which, on the one hand, guarantees the smooth operation of applications at times of peak load, and on the other, generates real cost savings during periods of lower traffic. In turn, self-repair mechanisms, which automatically restart failed containers and move applications from failed servers, ensure unprecedented high availability and resilience to hardware problems.

Another extremely important benefit is infrastructure independence. Since Kubernetes is an open-source standard, applications prepared to run on it can be easily moved between different environments - from your own server room to the AWS cloud, from AWS to Azure, or run in a hybrid model. This gives companies tremendous flexibility and avoids dependence on a single vendor (so-called “vendor lock-in”). Finally, efficient use of resources, thanks to smart scheduler, allows more applications to run on the same infrastructure, which directly lowers the total cost of ownership (TCO).

How to take care of the security of a Kubernetes cluster and the applications running on it?

Kubernetes, as a complex distributed system, introduces new paradigms, but also new attack vectors. Securing it requires a multi-layered, end-to-end approach, which is often referred to in the industry as the “4Cs”- ** Cloud, Cluster, Container, Code**. This means that we need to take care of security at four, intersecting levels.

Level one is Cloud, or securing the very infrastructure on which the cluster runs. This includes hardening virtual machine configurations, securing network access and following security best practices recommended by the cloud provider.

Level two is Cluster. Here we need to secure the components of Kubernetes itself, especially its “brain,” the control plane. It is crucial to implement strong authentication for API server access, use granular role-based authentication (RBAC) and define network policies (Network Policies). These act as the cluster’s internal firewall, precisely controlling which applications (more specifically, Pods) can communicate with each other.

Level three is Container. Security at this level involves taking care of the hygiene of the container images themselves. They should be built with minimal, trusted base images, regularly scanned for known vulnerabilities in the libraries they contain, and run with as few privileges as possible, avoiding, for example, running processes as the “root” user.

Level four is Code, which is the security of the application itself running in the container. This is classic application security, including protection against OWASP Top 10 vulnerabilities, use of secure programming practices and proper management of secrets such as passwords or API keys.

What does Kubernetes’ architecture look like and what are its major components?

Understanding the basic architecture of Kubernetes, while technical, is helpful in appreciating how it works. A Kubernetes cluster consists of two main types of machines: control plane nodes and working nodes.

  • The Control Plane is the “brain” of the entire cluster. This is where all global decisions are made. Its key components are the API Server (the front door to the cluster), etcd (the vitally important database that stores the entire state of the cluster), the Scheduler (which decides where to put new applications) and the Controller Manager (which runs control loops that take care of maintaining the desired state).
  • Worker Nodes are the machines on which our containerized applications actually run. Each Worker Node runs an agent called Kubelet, which communicates with the control plane and manages the containers on its machine.

What to look for when choosing a cloud provider to host Kubernetes?

Starting and maintaining your own Kubernetes cluster from scratch is an extremely complex task. That’s why the vast majority of companies choose to use managed Kubernetes services offered by major cloud providers such as Amazon EKS, Google GKE or Azure AKS. In this model, it is the cloud provider that takes all the responsibility for installing, managing and securing the complex control plane. When choosing a particular provider, it is worth considering factors such as the pricing model, the level of integration with other services of a given cloud (such as identity management systems or networks) and the flexibility of configuration.

How to monitor the performance and health of applications running on Kubernetes?

Monitoring a dynamic environment like Kubernetes requires modern tools. A stack based on open-source solutions has become standard in the cloud world: Prometheus for collecting detailed metrics from the cluster and applications, and Grafana for creating advanced, interactive dashboards that visualize this data. Complementing this stack are systems for centralized log collection and analysis.

What are the most common mistakes and challenges when implementing Kubernetes in an organization?

Despite its enormous potential, the road to mature use of Kubernetes is fraught with pitfalls. Among the most common challenges are underestimating its complexity and steep learning curve, ignoring security aspects by using default, unsecured configurations, failing to control costs in a flexible cloud environment, and trying to manage a cluster without having a dedicated, skilled platform team.

How to automate the process of deploying applications on Kubernetes using CI/CD?

Kubernetes and CI/CD pipelines are a perfect duo, made to work together. In the modern development process, a change in the application code automatically starts the process of building a new container image. Then, a continuous delivery (CD) tool, such as Argo CD, automatically deploys this new version to the Kubernetes cluster, often in a seamless and uninterrupted manner (rolling update), ensuring that innovations are delivered instantly to production.

How much does it cost to maintain a Kubernetes-based environment and how to optimize expenses?

The total cost of maintaining a Kubernetes environment consists of several elements: the control plane management fee (for managed services), the cost of the virtual machines that make up the working nodes, and the costs associated with network traffic and storage. The key to optimization is active management, the use of automatic scaling mechanisms and the conscious selection of the right types of resources to meet application requirements.

How can nFlo’s experience in cloud infrastructure management (AWS) and security support your company in deploying and maintaining Kubernetes?

Kubernetes is a powerful platform that can revolutionize the way your company builds and delivers software. But deploying, securing and maintaining it is a complex challenge that requires deep, interdisciplinary knowledge at the intersection of cloud, networking, automation and cybersecurity. At nFlo, we specialize in helping organizations with this transformation.

  • Cluster Design and Deployment: We design and deploy secure, scalable and cost-optimized Kubernetes clusters from the ground up, primarily based on Amazon’s EKS managed service, using best practices in architecture and configuration.

  • Securing Clusters: We perform comprehensive security audits of existing clusters, implement network policies, access control mechanisms (RBAC) and integrate container scanning tools to ensure the highest level of protection.

  • CI/CD Deployment and Automation: We help build modern CI/CD pipelines that automate the process of deploying and testing applications on Kubernetes.

  • Management and Optimization: We offer management and monitoring services for your Kubernetes clusters, ensuring their stability, performance and cost optimization.

Transforming to containerization and orchestration is a strategic decision. Contact the experts at nFlo to discuss how we can support you at every stage of your journey with Kubernetes - from strategy and design, to implementation, to secure and effective management.

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Frequently asked questions

What is Kubernetes and what problem does it solve?

Kubernetes is an open-source container orchestration platform originally developed by Google that automates the deployment, scaling, and management of containerized applications. It addresses the challenge of running hundreds or thousands of containers reliably across multiple servers by handling scheduling, self-healing, load balancing, and rolling updates automatically. Without Kubernetes, managing containerized environments at scale would require enormous manual operational effort.

What are the core components of a Kubernetes cluster?

A Kubernetes cluster consists of a control plane and worker nodes. The control plane includes the API server, etcd data store, scheduler, and controller manager that manage the overall cluster state. Worker nodes run the actual application containers through the kubelet agent, kube-proxy for network routing, and a container runtime such as containerd. Pods are the smallest deployable units, typically containing one or more containers sharing network and storage resources.

What security considerations are most important in Kubernetes environments?

Kubernetes security requires attention at multiple layers including cluster configuration hardening, role-based access control, network policies to isolate workloads, secrets management for credentials, image scanning before deployment, and runtime threat detection. Misconfigured RBAC permissions and exposed Kubernetes dashboards have been responsible for major cloud security breaches. Regular security audits of cluster configurations are essential to maintain a strong security posture.

When should a company consider using Kubernetes?

Kubernetes is most valuable when an organization runs multiple microservices that need independent scaling, requires high availability with automatic failover, or manages frequent deployments across different environments. For simple single-service applications or small teams without dedicated DevOps expertise, the operational complexity of Kubernetes may outweigh its benefits. Managed Kubernetes services from cloud providers such as EKS, AKS, and GKE reduce this burden significantly.

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