Difference between virtualization and containerization

Data canters consist of a large number of enterprise servers. Not all servers are active at the same time. In case traffic is directed mostly to a particular set of servers more, those servers get busy. The other servers are less loaded, or they even turn totally inactive, thereby wasting power, maintenance costs, and other allied resources.

With the changing times, businesses started looking for solutions to reduce overhead costs, enhance scalability, and standardize application deployment process. They started considering the following two approaches to reduce costs −

• Virtualization − Virtualization is the technology that can simulate your physical hardware (such as CPU cores, memory, disk) and represent it as a separate machine. It has its own Guest OS, Kernel, process, drivers, etc. Therefore, it is hardware-level virtualization. Most common technology is "VMware" and "Virtual Box".

• Containerization − Containerization is "OS-level virtualization". It doesn't simulate the entire physical machine. It just simulates the OS of your machine. Therefore, multiple applications can share the same OS kernel. Containers play similar roles as virtual machine but without hardware virtualization. Most common container technology is "Docker".

Go through this article to find out how Virtualization is different from Containerization.

What is Virtualization?

Virtualization is the process of partitioning a physical server into multiple virtual servers. The process of partitioning is carried out using a software called 'hypervisor'. After partitioning, the virtual servers act and perform just as a physical server. Essentially, it means using the same hardware set-up more efficiently, thereby freeing the resources for other tasks or retiring the resources altogether.

For example, instead of dedicating 1 server and 1 operating system to execute 1 dedicated task, the same server is partitioned such as 1 server and 2 operating systems, which can allow independent tasks running on each of them.

What is a Hypervisor?

A hypervisor, also known as Virtual Machine Monitor (VMM), is a software program that executes on a computer to manage multiple VMs.

A Hypervisor creates an abstract layer on the computer hardware, handles resource allocation, and monitors the virtual machines.

Types of Virtualizations

A wide variety of IT resources can be virtualized, as mentioned below −

• Application − An application is installed on a central server, which is accessible on various computers connected to the server. The virtual application works just as an application locally installed on the users’ physical computers. It is used to fix the bugs or update features centrally by accessing the application from multiple devices connected to the server. The system admin can change access permissions for just one application centrally. Application virtualization saves effort and time required for Installation of the application each time on users’ respective local computers.

• Desktop − A hypervisor is installed on a host machine or over an operating system. Virtualized desktops run on a remote server. Thus, each desktop can have a distinct OS. Virtualization enables R&D teams to develop or test applications on different operating systems.

• Network − Entire network setup is virtualized and managed as a single entity. This virtualization increases network performance, enables the system admins to allocate network resources effectively, and provides scalability of the devices in the network.

• Server − Here, the resources of a single server are partitioned into multiple virtual servers, which can run on computers with different OSs independently. It saves the hardware cost of keeping multiple physical servers.

• Storage − All physical storage media in an enterprise are presented as a single consolidated logical storage available centrally. Storage virtualization reduces the amount of hardware that is required to achieve the data and enables system admins to back-up and recover the data quickly.

Advantages of Virtualization

Following are some of the notable advantages of virtualization −

• Enhanced performance

• Promotes agile IT infrastructure

• Promotes use of resources in optimum manner

• Better disaster management if any physical hazards take place to resources

• Better security as the infected VM can be isolated from other VMs and the host server

• Space saving

• The capital investment cost on hardware is saved, and thereby maintenance cost is saved, hence overall cost savings for a business.

Now let us see what Containerization is and why it is required.

What is Containerization?

When code is developed in a specific computing environment and transferred to a different environment, there is a high possibility of the code to result in bugs and errors due to missing dependencies, libraries, or any configuration setting files.

For example, if a Windows-based version was ported to Linux operating system, or when an application was developed in the business environment and ported to the customer’s environment, the application would often throw errors. If the dependencies are provided along with the code, the potential bugs and errors can be eliminated.

Containerization is the process of bundling the application code along with the libraries, configuration files, and dependencies required for the application to run cross-platform.

Thus, Containerization is an application-packaging approach where the code is written once and capable of executing anywhere, making the application highly portable. This itself is an advantage of containerization. Docker is the example of a containerization platform.

What is a Container?

The single package of software built using containerization technology is called a ‘Container’. The container is a standalone package, independent of the host operating system. Being as such, it can then execute across multiple platforms, without any issues.

Following are the advantages of using Containers −

• Containers share the machine’s operating system Kernel. They do not require to associate the operating system from within the application hence they are lightweight.

• It takes less start-up time in the environment where it is deployed.

Difference between Virtualization and Containerization

The following table compares and contrasts the different features of Virtualization and Containerization −

Conclusion

Virtualization and Containerization are very similar yet different IT resource virtualization technologies. Both the technologies enable improved resource utilization with physical machines.

Virtualization supports executing multiple operating systems on a single physical server, whereas Containerization supports deploying multiple applications developed in the environment of one operating system residing on a single virtual machine or a server. Both the technologies address different challenges, hence the latter will not replace the prior.