What is Kubernetes?
Kubernetes is an open-source project that has become a widely used container orchestration tool, allowing for large-scale deployment and management of multi-container applications. While it is commonly used with Docker, the leading containerization platform, it is compatible with any container system that adheres to the Open Container Initiative (OCI) standards for container image formats and runtimes. Due to its open-source nature and minimal usage restrictions, it can be utilized freely by anyone who wants to run containers in any location - on-premises, public cloud, or a combination of both.
What are the benefits of Kubernetes?
Kubernetes has built-in commands that handle the majority of the work required for application management, enabling automation of day-to-day operations and ensuring applications are running as intended.
Kubernetes handles your workloads' computing, networking, and storage, allowing developers to focus on applications without worrying about the underlying environment.
Service health monitoring:
Kubernetes constantly monitors the health of services, restarting failed or stalled containers, and making services available to users only when it has confirmed they are running.
Google and Kubernetes
Kubernetes originated as a project at Google, and it is a successor to Google Borg, an earlier container management tool used internally. Google open-sourced Kubernetes in 2014, as the distributed microservices architectures facilitated by Kubernetes make it easy to run applications in the cloud. Google sees the adoption of containers, microservices, and Kubernetes as potential drivers for customers to use its cloud services. However, it works with Azure and AWS as well. Kubernetes is currently maintained by the Cloud Native Computing Foundation, which is under the Linux Foundation.
Kubernetes vs. Docker
Kubernetes and Docker are often mistakenly perceived as mutually exclusive alternatives when they are different yet complementary technologies for running containerized applications.
Docker allows the packaging of everything needed to run an application into a container that can be stored and opened. Once you begin packaging your applications, you require a means to manage them; that is where Kubernetes comes in.
Kubernetes, "captain" in Greek, acts like a ship's captain, responsible for safely transporting and delivering those containers to where they are needed.
- Kubernetes can be used independently or in conjunction with Docker
- Rather than being an alternative, Docker is typically used with Kubernetes to containerize and run applications at scale, making it less of a "Kubernetes vs Docker" comparison.
- The distinction between Docker and Kubernetes lies in their respective roles in containerizing and running applications.
- Docker is an open-industry standard for packaging and distributing applications in containers.
- Kubernetes employs Docker to deploy, manage, and scale containerized applications.
What is Kubernetes used for?
Kubernetes is utilized to create manageable applications that can be deployed anywhere. Kubernetes provides various options to suit your needs when offered as a managed service. Some common use cases include:
Increasing development velocity
Kubernetes helps construct cloud-native microservices-based apps and supports the containerization of existing apps, becoming the foundation for modernizing applications and allowing for faster development.
Deploying applications anywhere
Kubernetes is designed to be used anywhere, enabling applications to run across on-premises, public clouds, and hybrid deployments, making it possible to run applications where needed.
Running efficient services
Kubernetes can automatically adjust the size of a cluster required to run a service, allowing for automatic scaling of applications based on demand and running them efficiently.
Kubernetes architecture and how it works?
Containers encapsulate an application in a form that's easy to deploy and portable anywhere. The Kubernetes architecture is built to run containerized applications. A Kubernetes cluster comprises at least one control plane and at least one worker node (usually a physical or virtual server).
The control plane's main responsibilities are to expose the Kubernetes API through the API server and to manage the nodes that make up the cluster. The control plane makes decisions about cluster management and detects and responds to cluster events. The smallest unit of execution for an application running in Kubernetes is a Kubernetes Pod, which comprises one or more containers. Kubernetes Pods run on worker nodes.