It is truly hard to ignore names like Docker vs Kubernetes when we talk about cloud computing. Businesses across the globe are migrating their architecture and infrastructure towards cloud-driven systems.
As we have mentioned the names Docker vs Kubernetes, cloud computing, containerization, and container orchestration are also quite obvious names to indulge in.
Both docker vs kubernetes differences have transformed how they revolutionized the developing and deploying of software processes greatly. They are the technologies that helped in the smooth running of applications with Linux containers. However, from a closer look, you will find both the technologies work on different layers of the stack and then can be used together.
No matter if you are a mobile app developer, or product manager, data scientist, or someone else, both these cloud technologies will help you reach the desired goal.
Kubernetes- a container orchestration platform and Docker- the containerization platform are the tools you can’t substitute with another thing. So, if you are willing to get started with building a modern cloud infrastructure or willing to invest in the same, it is good to look at what docker vs kubernetes are and at the same time how they are different from each other.
Before getting started with what these technologies are able to let you achieve, let a look at top cloud computing trends for an understanding.
Now that you are done with the basic understanding of cloud computing and the emerging trends of it, let us begin the topic from the very scratch, i.e- Container in this docker and kubernetes the complete guide.
What Is A Container?
In a simple language, containers are a way to package software. They are highly used because when one runs the containers, they exactly know how it will run. Thus, containers are highly predictable, immutable, and repeatable.
Also, there are no sudden errors that arise with it even after moving it to the new machine or fitting it between environments. The required application’s code, dependencies, libraries, and others are packed altogether in the container as an immutable artifact.
It feels like running a virtual machine without spinning the entire operating system. Thus, bundling the application in the container along with a virtual machine can improve the time significantly.
The aforementioned features and characteristics of containers make it an essential yet awesome tool for supporting modern cloud architecture. As organizations and industries are paving their way towards microservice architectures, containers on the other hand facilitate quick elasticity and separation of concerns.
Among all these, building a container with Docker is a different kind of deed. So, in order to understand how to build a container, let us first understand everything about Docker.
What Is Docker?
A Docker makes it convenient and simple for developers to work on a project by running the application in the same environment without OS dependencies as Docker provides its own Operating system.
Earlier, in the absence of Docker, developers used to send code to the tester, but the code does not run on the tester system because of further dependencies.
But after the integration of Docker, testers, and developers can have the same system for running the Docker container. And with the help of Docker, both developers and testers can run the application in the same environment while eliminating the need for dependency issues.
Taking the flow into the technical form then Docker is a containerization platform packing the application and all related dependencies together in the form of a docker container.
It is a platform as a service product made exclusively for solving challenges that emerge from the DevOps trend. Docker makes the process easier for creation, deploying, and further running applications with containers.
Containers are something that made Docker easier and appealing for the developers. With the abstraction of the app layer, it packages the application and other dependencies for running applications like OS, application code, system tool, system libraries, runtime, and so on.
How To Build A Container With Docker?
Dockers are required to make you create and deploy software within the containers. It’s an open-source collection of tools helping developers to build, ship, and run the app, anytime, anywhere.
Using Docker, developers can easily create files called Dockerfile. The files further define the building process, which when fed to the “docker build” command produces an immutable docker image. It can be said as an application snapshot, given into the life-like form.
For starting up the process, use the “docker run” command for running anywhere the docker daemon for support and running. It can be made into the laptop, used in a production server like in Cloud, or on a raspberry pi.
Other than that, Docker also provides a cloud-based repository named Docker Hub. It is the same as GitHub when it comes to Docker Images.
Containers can also be made using Kubernetes too.
To understand how containers can be built with Kubernetes, let us understand what is Kubernetes with example.
What Is Kubernetes with example
Kubernetes is quite a powerful container management tool automating the deployment and management of containers. It has brought a big wave in cloud computing for developers.
Now, for running containers in production, one can have dozens even thousands of containers over time. The containers are then required to be deployed, managed, connected, and further updated even manually.
How To Build Containers With Kubernetes
Docker is great however it still has something missing in it like if you want to run multiple containers across multiple machines, then you need to use microservices.
Thus, for starting the container at the right time, developers need to talk to each other along with figuring out how to handle storage considerations while dealing with the failure containers or the hardware.
Doing all these processes manually is a tiresome job and to aid the cause, Kubernetes takes the charge.
It is an open-source container orchestration platform allowing large containers to work together while reducing the operational costs too. It simply helps in things like-
- Running containers for different machines
- Scaling up or down either by removing or adding containers as per the demand.
- Keeping storage consistent with multiple instances of the application.
- Equal distribution of load between containers.
- Launching new containers for different machines.
Now that we understand the basic concepts of containers and how it can be made with Docker and Kubernetes, it is now the time to look at the difference between both of them too.
What Is The Difference Between Docker vs Kubernetes
In a layman language, both of these technologies are designed to work together to ease the process of developers. As they are made to ease the work of developers for different levels and purposes, thus, they are not the competitors to each other.
Thus, cutting the chaos, the questions like “should I use one over another”, “which one can help you solve the problem faster”, “Which one is better” and so on shouldn’t arise. They both carry their separate roles in DevOps and are usually used together for great results.
However, the minor docker vs kubernetes difference is-
Docker– It is used for isolating the application into containers and then packing the app and shipping it.
Kubernetes– It is on the other hand known as a container scheduler. It is used for deploying the scaling application.
So, till now we are filled with the basic and core understanding of Docker, Kubernetes, and Containers, it is now the time to look at their advantages and disadvantages in this docker and kubernetes tutorial.
Advantages Of Docker
Efficient Use Of System Resources
Apps that are containerized consumes less memory as compared to virtual machines, and can be packed densely on to the hardware.
However, the cost-saving thing is also dependent on what kind of apps are used and how much resource-intensive it can be. For easing the process, containers work more efficiently as compared to virtual machines.
The containers can save the cost of software licenses.
Faster Software Delivery Cycles
It is crucial for an organization’s software to respond quickly to the changing conditions while meeting the scaling demand and easy updates to add new features.
For further processing, Docker containers make it easy to put new versions of software with new integrated business features into production instantly while quickly rolling back the previous version whenever required.
Easy Application Portability
For running enterprise applications while keeping things close and secure, or even in the public cloud for public access and high elasticity of resources.
Thus, for making the process easier, Docker containers encapsulate everything in an application for running and allowing it to revolve easily between different environments.
Developers with Docker runtime installed, they can run Docker containers easily.
For Microservices Architecture
Dockers make it easy for building software for forward-thinking lines as it is lightweight, portable, and self-contained. This will result in making developers solve tomorrow’s problems with yesterday’s methods.
The software patterns containers also make it easier for microservices for coupled components. By decomposing the traditional “monolithic” applications approach into separate services, microservices on the other hand then allow different parts of the line of business app scales, measured, modified, and services separately through different teams and timelines.
Docker Rapid Deployment
Docker can decrease the deployments time into seconds due to the fact that it can create separate containers for every process without booting an OS. Also, the data can be created easily with the access of destroying it when required.
With the help of Docker, applications that run on Docker can be segregated completely and isolated from each other from every point, be it from the security point of view while granting full control over traffic flow and management.
Using Docker, developers can build container images and can be later used for every step of the deployment process. Due to its separate non-dependent steps, running the process can be made nicely.
Disadvantages Of Docker
Docker Is Not A Problem Solver
Software that is stored in a container is more secure as compared to the software run on bare metal. Containers are great for adding layers of security for better results.
Docker Fails To Turn The App Into Microservices
When you containerize the existing app, it simply reduces resource consumption and further eases the deployment process. However, the process does not make any changes to the app design and its interaction with the other apps.
All these benefits come from the developer’s expertise and are not mandatory with the containers provided.
Dockers Are No Substitute For Virtual Machines
One of the top myths often heard of Dockers is that they make VMs obsolete. There are many apps that can run in a VM and further be moved into a container. However, this does not mean that any app can be moved to a container.
It Got Some Missing Features
There are a lot of feature requests that go under progress. For instance- container self-registration, copying files, self inspects, from host to container, and many others. Thus, the docker got some missing features.
Data In The Container
There are chances when the container might go down and requires a backup or maybe a recovery strategy. Thus, in such a situation, Docker can be a bet.
With it, let us know have a look at how Docker is made and what components are taken into it to make it what it is.
What Is Docker Concepts
There are three basic concepts that go for Docker namely-
Containers are the need to run and host in Docker and isolated machines or virtual machines can be taken into consideration for the process.
If you look from the conceptual POV, then a container runs inside the Docker host isolated from other containers and also without host OS. Containers cannot see others, any physical storage, or getting incoming connections until you made the connection.
They include everything that requires to run- OS, runtime, files, environment variables, standard input, output, and others.
A typical Docker server looks like a host of many containers like-
Containers are run from an image and an image describes everything which is required for the container created. It is basically a template for containers. Also, you can also create a number of containers as per the requirements that too from the single image.
The picture of it looks like-
All the images made are stored in the registry. The above image shown is used for creating two containers.
Each of the given containers has their own life and both of them share the common root.
Concluding the chapter of Docker, let us quickly look at who is using it for uplifting their work process.
Who is Using Docker?
The initial phase of the GE appliances technology and process integrated with cloud-based tools turned out to be difficult to use.
Thus for making their process good enough and quick, they switched to Docker, making developers finding it easy to use and adopted it quickly. They built services around Docker with greater density applications possible with virtual machines.
Also, Docker provided GE with support for legacy applications while speeding up migration from old legacy data centers.
For the BBC, the problem was speed and volume for the news division. Broadcasting news in 30 different languages with over 80,000 daily news items in English alone. Also, it ran over 26,000 jobs in ten different integration environments with sequential scheduling creating logjam while exceeding the run time up to 60 minutes.
To eliminate the issue, BBC turned to Docker which allowed the news channel to simply eradicate wait timing and run jobs in parallel. Other than that, Docker aided developers for a flexible continuous integration environment for easy working allowing them to have greater control over application architecture.
Lyft, one of the topmost known on-demand transportation companies. The app it had developed was monolithic and large with development and maintenance problems followed. Due to ineffective flexibility and self continued environments, Lyft transition was limited.
Thus, when Lyft made its architecture using Docker, it made developers test and deploy features independently while managing communication between microservices. Altogether, Docker resulted in faster and efficient development & delivery.
The on-demand taxi booking application organization is now using Docker for managing their continuous integration chain.
With it, let’s now move to Kubernetes’s advantages.
Advantages Of Kubernetes
Portable & Scalable
Kubernetes are designed to work upon one or more public cloud environments, virtual machines, or on bare metal for deploying infrastructure. Other than that, it is also compatible with other several platforms making multi-cloud strategy flexible and usable.
Also, it serves the purpose of workload scalability by offering features like –
- Horizontally infrastructure scaling
- Replication controller
- Manual scaling
Kubernetes does have the potential of handling both the infrastructure and applications. It helps in looking at several sides like-
- Constant check on the health of containers and modes.
- Its load balancer swiftly distributes the load across multiple loads.
The containerization does have the capability of speeding up the process of building, testing and later releasing software while including features like-
- Automated rollbacks and rollouts by handling the new version and app updates without downtime keeping a check on the health during rollout.
- It tests the new deployment production without skipping the previously made deployment too.
- It supports many top programming languages and mobile app development frameworks like .NET, Java, and others while supporting the development community too.
With it, let us now have a look at the concepts made by Kubernetes.
What Are The Concepts Of Kubernetes
The lowest unit of any application made in Kubernetes is called Pods. Pods on the other hand are not equal to a container in the Docker instead it can be made into various containers.
A pod carries-
- Single IP address
- Localhost sharing option
- IPC space
- A shared network port range
- Shared volumes
If you are willing to have three different versions of the same pod, in such a situation a Replicasets controller enters.
Replica Sets controllers are used for preventing any failure and top pod resource type and control it.
If you are willing to have connectivity to the pods, you need to have a service too. Kubernetes, have a service network abstraction over a set of pods. This overall helps for traffic to be balanced for failures.
Furthermore, Kubernetes got a single DNS record for the pods.
Above replica set sits deployment resource with the potential of manipulating the process. The manipulation here got some name because it is useful when it comes to upgrading the replica set. This then results in downtime.
Thus, Kubernetes deployments give developers the functionality to make upgrades without downtime.
The Kubernetes Architecture
The Kubernetes Architecture and its components
The primary control that managed workloads and communication across the system. Components inherited into it consist of different processes that can run single or multiple master nodes. The components it has been-
- Etcs Storage for storing configuration data of the cluster
- API server for the central management entity.
- Scheduler for scheduling pods on various nodes.
- Controller manager for running a number of distinct controller processes in the background.
Also known as Kubernetes or Minion Node, it contains the information for managing networking between containers.
- Kubelet ensures if all the containers in the node are running in a healthy state or not.
- Containers are called the lowest level of microservice for the inside of the pod and external IP address.
- Kube proxy works as a network proxy and also as a load balancer.
- cAdvisor acts like assistance for monitoring and gathering data.
Completing all the Kubernetes, it is now the time to look at the examples of it-
Where Is Kubernetes Used?
Pokemon Go, the online multiplayer game is one of the known games across the globe enabled with Kubernetes. Its release brought a lot of traffic for it and with Kubernetes, Pokemon Go got its popularity in the market with unexpected demand.
Pearson, one of the best known global education companies, is serving over 75 million learners with a goal of reaching around 200 million by 2025.
However, with more number of learners associated with it, it was challenging to adapt to the online audience’s needs. For that matter, they were required as a platform for helping them scale and adapt the online audience and deliver what they desire for in no time.
Thus, opting for Kubernetes helped them through container orchestration due to flexibility. And after integrating Kubernetes for their platform, they witnessed improvements in terms of productivity and delivery speed.
The topmost social networking platforms have a set of tools, platforms, and have grown into 1000 microservices. As it was growing, the company wanted to let its production fast without making developers think about the infrastructural process.
Thus, for simplifying their overall deployment and management of complicated infrastructure, Kubernetes came to the rescue. After its integration into the social networking system, Pinterest was able to reduce its build time without compromising efficiency.
With everything explained in this docker and kubernetes complete guide for the applications, Duber and Kubernetes are being highly used by the organization and well-known enterprises. There is a lot more information about the technology still remaining if you are still willing to know, connect with our experts to know more.
A technocrat and an entrepreneur who is the Co-Founder and Chief Delivery Head at Appventurez. Skilled in object-oriented programming (OOP), iOS Development, Design Principles, Data Structures, and Swift, he has served different organizations as Tech Lead.
⚡️ by Appventurez
Hey there! This is Chandrapal, author of this blog. Leave your email address and we'll keep you posted on what we're up to.
This will subscribe you to Appventurez once-a-month newsletter. You can unsubscribe anytime. And we promise not to pester you or share your data :)