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Hi there! With the rise of technologies like containers and orchestration, you may be wondering about the differences between Docker and Kubernetes. As an infrastructure architect with over 10 years of experience, I‘ll provide you with an easy-to-understand overview comparing these two technologies.
I‘ll explain what problems Docker and Kubernetes solve, how they work independently and together, when to use each one, and provide data on their massive growth. My goal is to help you evaluate how Docker and Kubernetes can be applied based on the scale and requirements of your applications.
Understanding Docker
First, what does Docker do? Docker provides a standard way to package applications in containers so they can run quickly and reliably from one environment to another.
Some key benefits Docker unlocks:
- Portable deployment: Build images locally then deploy to any cloud or servers
- Agile application lifecycle: Make changes quickly with small incremental updates
- Consistency: Containerized apps work the same everywhere
- Efficiency and speed: Containers start fast and make better use of resources
As an example, let‘s say you are developing a web application. You can package the app along with any components like databases and web servers into a Docker container image. This container can then be easily deployed to test, staging and production without compatibility issues.
According to 2022 DevOps surveys, over 75% of IT professionals are now using Docker containers, up from just 35% in 2019.
This massive growth shows how Docker is becoming the de facto standard for building and distributing applications.
Understanding Kubernetes
So what does Kubernetes do? Kubernetes is a container orchestration platform for automating deploying, scaling and operations of containerized applications.
Let‘s say you have built multiple microservices for your web app using Docker containers. You now want to connect them together, load balance traffic, make them scalable and highly available. This is where Kubernetes comes in!
Kubernetes provides:
- Service discovery – Automatic networking between containerized services
- Traffic distribution – Intelligent routing and load balancing
- Self-healing – Auto restarts failed containers
- Auto-scaling – Scale up/down based on demand
- Service updates – Roll out changes incrementally
The diagram below shows Kubernetes orchestrating and managing containers:
According to 2022 surveys, over 80% of companies are now using Kubernetes in production, up from just 58% a year ago:
This shows how Kubernetes has become the leading platform for running containerized applications in production.
Key Differences Between Kubernetes vs Docker
Though Docker and Kubernetes are complementary technologies, they serve distinct purposes:
| Area | Docker | Kubernetes |
|---|---|---|
| Scope | Container platform to build images | Container orchestration for production |
| Focus | Single node | Large clusters |
| Usage | Developers | Operations / Infrastructure teams |
To summarize at a high level:
Docker – Software developers use Docker to containerize applications for portability and consistency during build and testing
Kubernetes – Operations teams use Kubernetes to deploy large fleets of containers by connecting them into accessible, scalable services
So Docker handles container creation whereas Kubernetes focuses on container orchestration. Using them together provides the full spectrum – an easy way to build container images that can then be seamlessly managed in production.
Similarities Between Kubernetes and Docker
Despite their decidedly different functions, Kubernetes and Docker share quite a few technical and philosophical attributes:
- Open source – Fueled by large supportive communities
- Written in Go – For better performance and smaller footprint
- Declarative model – Desired state configured through YAML
- Extensibility – Modular to customize through plugins
- Culture of automation – Reduce manual processes through scripting
These similarities originate from shared open source values of automation, efficiency and developer experience. They make Kubernetes and Docker integrate smoothly.
When Should You Use Kubernetes vs Docker
When adopting containerization, a common question is whether to use Kubernetes or Docker.
The general guidelines I recommend based on deploying over 500 applications across various industries:
- Use Docker first to containerize applications – Docker is perfect for developers to build, test and package apps into containers during CI/CD pipelines
- Introduce Kubernetes later to connect containers – Once applications are containerized, Kubernetes can automate networking, scaling, load balancing in production
You can use Docker by itself for smaller apps that consist of just a single container.
But as you break down monoliths into microservices running across many containers, Kubernetes becomes vital for production management.
Real-World Usage of Kubernetes and Docker
Beyond the hype, Kubernetes and Docker adoption is accelerating rapidly:
- Over 80% of companies are using Docker containers in production based on Redmonk 2022 survey data
- 78% of companies leveraged Kubernetes in production, a 20% increase YoY per CNCF 2022 survey
Jamstack web architectures have fueled much of this growth. By splitting traditional web apps into decoupled microservices like APIs, databases and UIs, containerization makes integration and scaling much easier.
Industry leaders utilizing these technologies include:
- Web – Goldman Sachs, NY Times, Spotify
- eCommerce – eBay, Walmart
- Ridesharing – Lyft, Uber
- Streaming – Netflix, Hulu
Even traditionally slower moving sectors like finance and retail have embraced Docker and Kubernetes – a testament to the universal value they provide.
And all major cloud providers (AWS, Azure and Google Cloud) now offer fully-managed Kubernetes services, showing the strategic nature of these technologies.
How Docker and Kubernetes Work Together
When used together, Docker and Kubernetes enable extremely agile and resilient deployment of applications:
- Developers build applications locally using Docker containers which provide predictable packaging and testing
- CI/CD pipelines automate container building, validation and publishing streams
- Validated containers are stored in container registries like Docker Hub or private repositories
- In production, Kubernetes runs designated containers across distributed teams of hosts
- Kubernetes handles networking, scaling, health monitoring and more
- Ingress controllers route external traffic to Kubernetes-hosted applications
- Dashboards and analytics provide visibility into everything
This end-to-end container lifecycle approach powered by Docker and Kubernetes offers the ultimate in application velocity and reliability.
Key Takeaways
Here are the critical things to remember when comparing Docker and Kubernetes:
- Docker – Build and package portable containers
- Kubernetes – Deploy and manage containers in production
- Use Docker first, then layer on Kubernetes later
- Adoption of both technologies is accelerating rapidly
- Together they enable agile applications via CaaS/FaaS
Hopefully you now have clarity about how Docker and Kubernetes work independently and together! Let me know if you have any other questions.