What Is a Virtual Machine, and How Is It Used?

Virtual Machine

A virtual machine, abbreviated as VM, is no different than any other actual computer, such as a laptop, smartphone, or server. It features a CPU, RAM, discs for storing your files, and the ability to connect to the internet if necessary. When it comes to virtual machines (VMs), they are commonly referred to as software-defined computers (SDCs) within physical servers because they exist only as code.

How does a Virtual Machine Work?

Virtual machines are enabled via virtualization technology. Virtualization employs software to replicate virtual hardware, allowing numerous virtual machines (VMs) to run on a single computer. The physical machine is referred to as the host, and the VMs that run on it are referred to as guests.

This operation is overseen by a piece of software known as a hypervisor. The hypervisor is in charge of managing and provisioning resources from the host to guests, such as memory and storage. It also arranges operations in VMs so that they do not compete for resources. No virtualization or resource sharing is possible without a hypervisor. In virtualization, two types of hypervisors are employed.

Type 1 hypervisors (also known as bare metal hypervisors) run on the underlying physical hardware. Virtual machines (VMs) communicate directly with hosts to allocate hardware resources, with no additional software layers in between. Host computers that run type 1 hypervisors are only used for virtualization. They are frequently encountered in server-based environments, such as enterprise datacenters. Citrix Hypervisor and Microsoft Hyper-V are two examples of type 1 hypervisors. To handle guest operations such as generating new virtual machine instances or controlling rights, a separate management tool is required.

They’re also known as hosted hypervisors, these types of hypervisors run right on top of the host computer’s operating system. Hosted hypervisors route VM requests to the host operating system, which allocates the necessary physical resources to each guest. Because every VM activity must first pass through the host operating system, type 2 hypervisors are slower than type 1 hypervisors. Guest operating systems, unlike bare-metal hypervisors, are not bound to physical hardware. Users can run VMs and continue to utilize their computers as usual. As a result, type 2 hypervisors are appropriate for personal users or small enterprises that do not have dedicated virtualization servers.

What are Virtual Machines used for?

Here are a few examples of how virtual machines are used:

  • Creating and deploying cloud-based applications.
  • Using a new operating system’s beta test version.
  • Creating a new environment for developers to conduct dev-test scenarios more quickly and easily.
  • The process of making a copy of your operating system.
  • Installing an earlier operating system allows you to access virus-infected data or execute an old application.
  • Using software or programs that were not developed for a certain operating system.

What are the Advantages of Virtual Machines?

As if they were separate computers, virtual machines have the advantage of not interfering with each other or the physical host machine. A piece of software known as a hypervisor or virtual machine management enables you to run several operating systems on many virtual machines concurrently. This enables the use of Linux virtual machines on a Windows operating system, for example, or the use of an older version of Windows on a more recent Windows operating system.

Additionally, because VMs are self-contained, they are exceedingly portable. You can nearly instantly migrate a virtual machine running on one hypervisor to another hypervisor running on a completely different computer.

Virtual machines provide numerous advantages as a result of their flexibility and portability, including the following:

Savings on infrastructure costs—by running many virtual environments on a single piece of technology, you can significantly reduce your physical infrastructure footprint. This benefits your bottom line by reducing the need for nearly as many servers and lowering maintenance and electricity expenditures.

Agility and speed—Spinning up a virtual machine is a reasonably simple and quick process compared to establishing an entirely new environment for your engineers. Virtualization significantly speeds up the process of conducting dev-test scenarios.

Reduced downtime—Because virtual machines are so portable and easy to migrate from one hypervisor to another on a different computer, they are an excellent backup solution if the host goes down suddenly.

Scalability—VMs enable you to scale your applications more simply by adding more physical or virtual servers and spreading the workload over numerous VMs. As a result, you may improve your apps’ availability and performance.

Benefits of security—Because virtual machines run under several operating systems, running a guest operating system on a VM enables you to execute applications with dubious security while protecting your host operating system. Additionally, virtual machines provide improved security forensics and are frequently used to securely investigate computer viruses by separating the viruses from their host computer.

There are two types of Virtual Machines

VMs are frequently classified according to the hypervisor used to manage them or the sort of workloads they support. However, virtual machines are also classified according to their type:

Process Virtual Machine 

Virtual machines for processing. A process virtual machine (VM) is a transient, platform-independent programming environment that is used to execute a single process as an application. The environment acts as a high-level abstraction, concealing the underlying hardware or operating system. When a process begins, a process virtual machine is created and destroyed when the process completes. Two popular process virtual machines are the Java Virtual Machine, which is included with the Java platform, and the Common Language Runtime, which is included with the.NET Framework.

Two popular process virtual machines are the Java Virtual Machine, which is included with the Java platform, and the Common Language Runtime, which is included with the.NET Framework.

System Virtual Machine 

Virtual machines for the system. A system virtual machine (VM) is a completely virtualized environment that runs its operating system and is housed on a physical server. The VM shares the physical resources of the host but provides a complete environment for running applications and services, much like a real machine does but without the overhead. System virtual machines rely on a hypervisor to virtualize and make available hardware resources to VM environments. A good example of a system VM can be used with virtualization platforms like VMware vSphere or Microsoft Hyper-V.