Demystifying virtualization, containerization, and Docker architecture

Rajeev Pandey
14 min readMar 2


Data Engineering

Well, let me tell you a secret: Developers are obsessed with data engineering because they love to spend countless hours cleaning up messy data, writing complicated ETL pipelines, and trying to figure out why their code is failing in production.

It’s like a puzzle that they can’t resist solving, even if it means staying up all night with nothing but a cup of coffee and a stack of error logs to keep them company. And let’s not forget the sheer thrill of finally getting that data to flow smoothly from one system to another.

But in all seriousness, data engineering is becoming increasingly important in today’s data-driven world. Developers who have a solid foundation in data engineering can create efficient and effective data pipelines that can provide valuable insights to businesses. Plus, it’s just really satisfying to see all that data flowing smoothly and accurately through your pipeline.

Before we go into more detail, I would appreciate it if you could review the prior article, as it will provide you with some background information to the entire DE Roadmap journey.

Data Engineering — Basic Introduction

Data engineers are in a unique position. They need to understand the basics of data engineering and be able to build their own solutions. This is because they work with data, which is often not easy to come by. In this post, I will explain why learning the basics of anything makes more sense, and then I will go into how understanding virtualization, containerization, and Docker architecture can help data analysts in their work.

Data engineering is a field that has its own jargon. It can be hard to understand when you’re just starting out, but it doesn’t have to be!

The basics of data engineering will help you understand the five main components of this field: virtualization, containerization, docker architecture, big data processing, and storage. There’s a lot of talk about data engineering these days. But in order to understand it, you need to understand the fundamentals.

If your “why” for learning data engineering is clear, then your “how” will be easy.
”Always remember, when the why is clear, the how becomes easy”

The best way to understand data engineering is to understand virtualization, containerization, and Docker architecture. This will help you understand how these technologies work and what they mean for your day-to-day job as a data engineer.

In this article, we will cover the following topics:

  1. What is virtualisation? How does it work?
  2. What is containerization? Why do we need it?
  3. What is Docker architecture? How does it work?

What is virtualization?

Virtualization is the process of creating a virtual version of something, such as a virtual machine or virtual network. In computing, virtualization is the creation of a virtual environment that simulates a physical computer or network, allowing multiple operating systems or applications to run on a single computer or server.

In today’s world, virtualization is crucial for businesses and individuals alike. It allows organizations to run multiple applications or operating systems on a single server, reducing hardware costs and improving efficiency. It also enables individuals to use multiple operating systems on a single computer without the need for additional hardware.

A real-time example of virtualization can be seen in cloud computing. Cloud computing is a technology that uses virtualization to make computing resources available over the internet whenever they are needed. Cloud service providers use virtualization to create multiple virtual machines on a single physical server, which allows them to provide scalable and flexible computing resources to their customers. Another example of virtualization is the use of virtual private networks (VPNs). A VPN is a virtual network that provides secure access to a private network over the internet. VPNs use virtualization to create a virtual network that simulates a physical network, allowing users to access resources on the network from anywhere in the world.

In real life, virtualization can be compared to a hotel. A hotel has a finite number of rooms, but it can accommodate multiple guests by assigning them to different rooms. Similarly, virtualization allows multiple operating systems or applications to run on a single server, just like how multiple guests can stay in a single hotel without disturbing each other.

What is a hypervisor?

In virtualization, a hypervisor (also known as a virtual machine monitor) is a piece of software that allows multiple virtual machines to run on a single physical machine. It provides an abstraction layer between the hardware and the virtual machines, allowing each virtual machine to believe it has exclusive access to the hardware resources.

There are two types of hypervisors: Type 1 and Type 2. Type 1 hypervisors run directly on the host machine’s hardware, while Type 2 hypervisors run on top of an operating system. Both types of hypervisors provide virtual machines with access to the host machine’s CPU, memory, storage, and other resources.

In the modern world, hypervisors are essential for a variety of reasons. They allow multiple virtual machines to run on a single physical machine, reducing the need for additional hardware and lowering costs. They also provide a level of isolation between virtual machines, enhancing security and making it easier to manage resources. Additionally, hypervisors enable the creation of virtual environments, allowing developers to test software and configurations without impacting the production environment.

Real-life instances of hypervisors can be found in cloud computing environments. Cloud providers such as Amazon Web Services (AWS), Microsoft Azure, and Google Cloud Platform use hypervisors to create virtual machines that can be rented by customers. These virtual machines provide customers with access to computing resources without the need to purchase and maintain their own hardware. Hypervisors also enable cloud providers to efficiently allocate resources and ensure the security of customer data.

While studying, I also created some notes on my iPad using the Goodnotes app. I am not sure whether they will be beneficial, but I am sharing them just in case.

My Ipad Notes — Virtualisation

Benefits of Virtualisation

Virtualization technology provides several benefits, including:

  1. Resource utilization: Virtualization allows for better use of available hardware resources by allowing multiple virtual machines (VMs) to run on a single physical server. This can help reduce hardware costs, power consumption, and data center footprint.
  2. Flexibility: Virtualization enables IT administrators to quickly and easily provision new VMs, move workloads between physical servers, and adjust resource allocations as needed. This flexibility can help organizations respond more quickly to changing business needs.
  3. Improved disaster recovery: Virtualization can make it easier to recover from a disaster by allowing VMs to be easily moved to a different physical server or even to a cloud provider. This can help minimize downtime and data loss in the event of a disaster.
  4. Better testing and development: Virtualization can provide a more efficient and cost-effective way to test and develop applications by allowing developers to create multiple VMs with different configurations and operating systems.
  5. Enhanced security: Virtualization can help improve security by isolating different workloads and applications from each other, reducing the risk of malware or other security threats spreading across a system.
  6. Legacy system support: Virtualization can allow organizations to continue running legacy applications on newer hardware by creating a virtual environment that emulates the old hardware and software environment.
My Ipad Notes

What Are Containers?

Containers are a great way to manage applications on your server. In this section, we will go over what containers are and how they work, as well as some of the benefits and downsides of using them.

Containers are lightweight, portable, and self-contained execution environments that can run an application and its dependencies consistently across different computing environments. They are used to package an application with all of its dependencies, libraries, and configuration files in a single, portable package. This makes it easy to deploy and run applications across different computing environments, including development, testing, and production.

What is a container used for?

Containers are commonly used in the development and deployment of microservices-based applications, cloud-native applications, and serverless architectures. They provide a convenient way to isolate and manage different components of an application, such as web servers, databases, and message queues, as independent containers.

To use containers, you first need to create a container image, which is a snapshot of an application and its dependencies. You can create a container image using a Dockerfile or a containerization tool, such as Kubernetes or Docker Compose. Once you have a container image, you can run it on any platform that supports containers, such as Docker, Kubernetes, or Amazon Elastic Container Service (ECS).

If you’re looking for a container image, the first thing to do is search the registry. You can do this by entering any of these queries:

  • Your specific application name (e.g., “redis”)
  • Your operating system (e.g., “centos”)
  • The type of operating system (e.g., “linux”)

The second thing to do is find the right image. When you search for a specific application, you’ll see all of the images that meet your criteria first. If there are multiple versions available, click on one of them and then read more about it before deciding if it’s what you want.

If you’re looking for a specific version of an operating system, it’s best to search for “ubuntu 16.04,” since this will give you the most accurate results. If there are multiple versions available, click on one of them and then read more about it before deciding if it’s what you want.

Where can I find the best container images on the registry?

You can find container images on a container registry, which is a centralized repository for storing and distributing container images. Docker Hub is the most popular container registry, but there are many other registries available, such as Google Container Registry, Amazon Elastic Container Registry (ECR), and Microsoft Azure Container Registry. You can search for container images on a registry and download them to your local system or use them directly in your container orchestration tool. When choosing a container image, it’s important to select one that is secure, up-to-date, and maintained by a trusted source.

What is a virtual machine?

A virtual machine (VM) is a software program or emulation of a computer system that behaves like a physical machine. It allows multiple operating systems to run on a single physical machine, creating a virtual environment that simulates the hardware and software of a real computer. It typically includes a virtual processor, memory, storage, and other resources that are allocated from the physical host machine. It also has its own virtual operating system, which allows it to run software applications and interact with other virtual machines on the same host machine.

In today’s world, virtual machines are used in various scenarios, such as software development, testing, server consolidation, cloud computing, and security. For example, developers can use virtual machines to create different development environments for different projects, without having to install and configure different operating systems or applications on their physical machines. Virtual machines can also be used to test software in various operating system environments or to create a sandboxed environment for security purposes.

Now, let’s compare virtual machines and containers in a point-by-point manner:

I hope this comparison helps you understand the differences between virtual machines and containers.

What exactly is a Docker, and why do we need one in the first place?

Docker is a software platform that enables developers to build, package, and deploy applications as lightweight, portable containers. These containers can run on any machine, whether it’s a developer’s laptop or a production server, without any additional configuration or dependencies.

Docker is designed as a client-server architecture, where the Docker client interacts with the Docker daemon or server to build, run, and manage Docker containers. The Docker client and server can run on the same machine, or the client can connect to a remote Docker server.

There are several reasons why developers might use Docker:

  1. Consistency: Docker containers provide a consistent environment for applications, ensuring that they run the same way across different machines and environments.
  2. Portability: Docker containers can be easily moved between machines and environments, making it easier to deploy applications across different environments and infrastructures.
  3. Resource efficiency: Docker containers are lightweight, using fewer resources than traditional virtual machines. This makes them ideal for running multiple containers on a single machine.

Docker Architecture

The architecture of Docker consists of several components:

  1. Docker daemon: The Docker daemon or server is responsible for managing Docker containers, images, and networks. The daemon listens for API requests from the Docker client and performs the requested actions.
  2. Docker client: The Docker client is a command-line tool that allows developers to interact with the Docker daemon. The client sends API requests to the daemon to build, run, and manage Docker containers.
  3. Docker registries: Docker registries are repositories for Docker images. They allow developers to share and distribute Docker images across different machines and environments.
  4. Docker images: Docker images are read-only templates used to create Docker containers. They contain all the necessary files and dependencies needed to run an application.
  5. Docker containers: Docker containers are lightweight, portable environments that run applications. They are created from Docker images and can be easily moved between machines and environments.

Docker is built on top of a few key concepts, including images, containers, and Dockerfiles.

Docker Object: A Docker object is a fundamental element that Docker uses to create and manage its resources. Docker has several different types of objects, including:

  • Images: A Docker image is a pre-built, read-only template that contains all the code and dependencies needed to run a specific application or service. It is the starting point for creating a Docker container.
  • Containers: A Docker container is an instance of a Docker image that can be run in isolation from other containers on the same system. Each container has its own file system, network interfaces, and system resources, making it easy to run multiple applications on the same server.
  • Networks: Docker networks provide a way for containers to communicate with each other and with the outside world. A Docker network can be used to isolate containers and provide a secure network environment for them to run in.
  • Volumes: Docker volumes provide a way for containers to store data persistently, even after the container has been stopped or deleted. Volumes can be shared between containers, making it easy to share data between different parts of an application.

Dockerfile: It is a text file containing instructions to build a Docker image, which is a complete package that includes dependencies, configurations, and application code required to run a specific service or application. Dockerfiles use simple syntax, such as FROM, RUN, and CMD commands, to specify the building steps. They are crucial for creating reproducible images that can be used to build containers, allowing applications to be easily moved across different environments. Dockerfiles are also helpful in automating the deployment process, allowing applications to be built, tested, and deployed consistently and quickly.

How Docker Creates a Container

  • Step 1: Create an Image To create a Docker container, you first need to create a Docker image. This involves creating a Dockerfile that includes all the necessary configuration settings and dependencies needed to run your application.
  • Step 2: Build the Image Once you have created your Dockerfile, you can use the docker build command to build the Docker image. This command reads the instructions in the Dockerfile and creates a new image that includes all the necessary components needed to run your application.
  • Step 3: Create a Container Once you have built your Docker image, you can use the docker run command to create a new container from the image. This command starts a new container based on the image and assigns it a unique ID.
  • Step 4: Manage the Container Once you have created your container, you can use a variety of Docker commands to manage it. For example, you can use the docker ps command to view a list of all the running containers on your system, or the docker stop command to stop a container that is currently running.

Docker Container Lifecycle Management

Docker container lifecycle management refers to the process of managing the various stages of a Docker container’s existence, from creation to deletion. This includes starting and stopping containers, managing their resources, scaling up or down as needed, and ensuring that they are always running smoothly.

The lifecycle of a Docker container can be divided into four stages: create, start, stop, and delete. During the create stage, a Docker image is used to create a new container with its own file system and network interface. The start stage is where the container is actually launched and begins running. The stop stage occurs when the container is gracefully shut down and all of its resources are freed up. Finally, the deleted stage involves removing the container from the system entirely.

To manage the lifecycle of Docker containers effectively, there are various tools and technologies available, such as Kubernetes, Docker Compose, and Docker Swarm. These tools provide features like automatic scaling, load balancing, health checks, and rolling updates to ensure that containers are always running optimally and are accessible to users.

In conclusion, I hope you found this introduction to virtualization and containerization informative and useful. Understanding these fundamental concepts is essential for developing a strong foundation in modern IT infrastructure and application deployment.

In the next blog, we will explore how to install Docker and provide you with some useful commands and examples to help you get started with containerization. By practicing these concepts and gaining hands-on experience, you can master the art of containerization and leverage its many benefits to develop and deploy applications with greater speed, efficiency, and scalability.

So keep learning, keep practicing, and stay tuned for more exciting insights and updates in the world of containerization and virtualization.

Conclusion :
Hey there, fellow data enthusiasts! If you’re hooked on my articles and can’t get enough of my witty data humor, then you’re in luck! Here are three ways you can stay connected with me:

A. Follow me on LinkedIn and join my network of awesome data professionals. You’ll never miss a beat when it comes to my latest stories, tips, and tricks.

B. Subscribe to my newsletter, the ultimate insider’s guide to all things data engineering and data visualization. You’ll get exclusive access to new stories, and you can even text me to ask all the burning questions you’ve been dying to know.

C. Become a referred member, and get ready to indulge in an endless buffet of data knowledge. You’ll never have to worry about hitting your “maximum number of stories for the month” limit again, and you’ll get to read everything that I (and thousands of other top data writers) have to say about the newest technology available.

So what are you waiting for? Let’s get connected and start exploring the exciting world of data together! Oh, and don’t forget to bring the coffee — it’s the secret ingredient to unlocking the full potential of your data brainpower. Cheers!

So come on, let’s dive deep into the wonderful world of data together! Check out my website at, connect with me on LinkedIn at, or shoot me an email at Can’t wait to hear from you!



Rajeev Pandey

I’m Rajeev, 3 X Tableau Zen Master , 5 X Tableau Ambassador, Tableau Featured Author, Data Evangelist from Singapore