Difference Between Docker and Virtualization

Years back when organizations were planning to transform their projects with emerging technologies like Cloud or On-Premises Server, they came up with two solutions i.e. Docker and Virtual Machines. Both of them were introduced to solve these organizational issues using Containers. They simplify the deployment process of applications and microservices. Let's understand the difference between both.

Docker:

The code doesn't work on the other system due to the difference in computer Environments. Docker is the world's leading software container platform.

• Docker is a tool designed to make it easier to create, deploy, and run applications by using containers.
• Docker containers are lightweight alternatives to Virtual  Machines and it uses the host OS
• You don't have to pre-allocate any RAM in containers.

Despite their apparent similarity to virtual machines, Docker containers have several significant distinctions. The OS is abstracted via containers rather than the hardware. With the use of containers, a developer can package up a program with all of its constituent elements, including libraries and other dependencies, and deliver it as a single package. To manage these packages, use the docker-compose file. You now have a variety of options for virtual machine storage and real-time communication thanks to the establishment of the Container Runtime Interface (CRI).

Virtualization :

A virtual version of something, such as an operating system (OS), server, storage device, or network resources, is created instead of the real-life counterpart. A virtual system is created by virtualization using software that mimics hardware capabilities. By using this technique, IT companies may run several operating systems, numerous virtual systems, and a variety of applications on a single server.

Advantages of Virtualization:-

1.  Virtualization technology provides a software layer to Servers, Storage, Network, Application, and IT Infrastructure by using a hypervisor.
2. Allows multiple virtual machines and applications to run on the same physical machine.
3. Provides greater flexibility
4.  Isolation from Hardware
5.  Easy Management of IT Infrastructure
6.   Reduce operating costs
7. Minimize downtime.
8.  Increase IT Productivity and efficiency
9.  Faster deployment and provisioning of IT resources
    

A valuable IT service may be produced by employing resources that are often restricted to hardware thanks to the technique known as virtualization. Distributing a physical machine's capabilities among several users or contexts enables you to utilize it to its maximum potential.

Docker Architecture:

The Docker Client, Docker Host, Network and Storage components, and the Docker Registry/Hub make up the client-server architecture of Docker. 

1. Docker’s Client: Clients are used by Docker users to communicate with the platform. Any time a docker command is executed, the client transmits the command to the docked daemon, which executes it. Docker commands utilize Docker API. The Docker client has the option of interacting with several daemons.
2. Docker Host: Applications may be executed and operate in a full environment thanks to the Docker host. Images, Containers, Networks, and Storage are included in it. It also includes the Docker daemon. The daemon, which manages all container-related operations, accepts commands from the CLI or the REST API, as was already explained. To administer its services, it can also talk to other daemons.

Docker Objects:

1. Image: A Docker container may be created using an image, a read-only template. Frequently, a picture is derived from another image and then modified somewhat. You might create an image based on the Ubuntu image, for instance, but install your program, the Apache web server, and the configuration information required to execute it.
2. Containers: A private container registry may be used to distribute container images amongst teams inside an organization. A public registry like Docker Hub can be used to share them with the entire world. Images are important to the Docker experience because they allow developers to collaborate in previously impossible ways.

Networks: All separated containers interact with one another using Docker networking. Five network drivers make up the majority of docker's drivers.

1. Bridge: The container comes with Bridge as its default network driver. When several Docker instances communicate with the same Docker host, it is utilized.
2. Host: The resources that are now executing on your local machine may be seamlessly integrated with Docker thanks to this driver. Low-level IP tunneling and data link layer encryption between Docker programs running on various endpoints are provided by relying on the built-in network capabilities of your computer.
3. None: All networking is disabled with this driver.
4. Overlay: Containers may connect with one another thanks to this kind of software-defined networking technology. You must first construct a virtual bridge on one host to link it to an external host, and then you must set up an overlay network. Additionally, you will need to set up the overlay network and authorize access from one side to the other.
5. macvlan: The macvlan driver may be used to give containers an address and make them look like real devices. Its use of MAC addresses instead of IP addresses to route communication across containers makes it distinct from other solutions. Use this network when you want the containers to appear as physical objects, such as during a VM setup migration.

Virtualization  Architecture:

A model that conceptually explains virtualization is referred to as architecture. The use of virtualization in cloud computing is essential. End users share data on apps known as the clouds in cloud computing. However, virtualization itself allows users to share the complete IT infrastructure. A hypervisor or virtual machine monitor (VMM) is a piece of computer software, firmware, or hardware that creates and runs virtual machines. System virtualization can be approached through hardware partitioning or hypervisor technology. It separates operating systems and programs from the underlying computer hardware so that the host computer may run numerous virtual machines (VM) as guests that share the system's existing computational resources, such as processor cycles, memory space, network bandwidth, and so forth.

Form 1: A bare-metal hypervisor is the initial type of hypervisor. They immediately run on top of the host system's hardware. They provide efficient resource management and guarantee plenty of resources. Direct access to the hardware system is provided, resulting in improved scalability, performance, and stability

Form 2: Instead of resting directly on top of the hardware like the type 1 hypervisor does, a type 2 hypervisor, sometimes referred to as a hosted hypervisor, is put on top of the host operating system. Every VM or guest operating system operates atop the hypervisor. Tasks involving system configuration and maintenance may be made simpler by the comfort of a well-known host OS.