From Kubernetes docs, Kubernetes, also known as K8s, is an open source system for automating deployment, scaling, and management of containerized applications.
It groups containers that make up an application into logical units for easy management and discovery. Kubernetes builds upon 15 years of experience of running production workloads at Google, combined with best-of-breed ideas and practices from the community.
Why Kubernetes is Both:
Container Management:
Kubernetes handles containerized applications (like Docker containers) by deploying, running, and managing them.
It works as the platform where your containers are launched and monitored.
Orchestration:
Kubernetes automates the orchestration of containers at scale, ensuring they are deployed, scaled, and maintained across a cluster of machines.
It provides load balancing, fault tolerance, and auto-healing, which are core orchestration functionalities.
What is a Container?
A container is a lightweight, portable, and isolated runtime environment for applications. It packages an application and its dependencies (libraries, binaries, and configurations) together so it can run consistently across various computing environments.
Key Features of Containers:
Isolation: Containers isolate the application from the underlying host system and other containers.
Portability: Containers can run on any platform that supports the container runtime (e.g., Docker, Podman).
Efficiency: Containers share the host OS kernel, making them lightweight compared to virtual machines.
Consistency: "Works on my machine" issues are eliminated as the container runs the same way in any environment.
Example:
Think of a container as a shipping container. Inside the container is the application and everything it needs to run (e.g., files, environment variables). Regardless of the ship (operating system), the container can be transported and operated anywhere.
likewise Docker is one among the best container management tool that helps to build a container out of your application or code.
What is Orchestration?
Orchestration refers to the automated management, coordination, and scaling of containers in a production environment. When you have multiple containers running different parts of an application, orchestration ensures everything works seamlessly.
Why Do You Need Orchestration?
Managing containers manually becomes challenging when:
You have multiple containers running across several servers.
You need high availability and scalability for your application.
You must handle container failures and ensure the application stays operational.
What Does Orchestration Do?
Deployment: Automatically deploys containers across multiple servers.
Scaling: Increases or decreases the number of containers based on demand.
Load Balancing: Distributes traffic across containers to ensure no single container is overwhelmed.
Health Monitoring: Monitors container health and restarts them if they fail.
Networking: Provides networking between containers, including service discovery.
Storage Management: Connects containers to storage resources.
How Do Containers and Orchestration Work Together?
Containers are the building blocks for running applications.
Orchestration tools (like Kubernetes) provide the automation layer to manage containers at scale.
Example:
You package your app in a container (e.g., Docker).
You use Kubernetes to deploy and manage those containers across a cluster of machines.
Kubernetes ensures your app is running even if a container crashes.
It automatically scales the app when traffic increases.
It provides networking between containers and external clients.