How do you define a virtual machine?

A virtual machine (VM) is a type of computing resource that functions more like a software-driven virtual machine than a physical computer. One or more virtual computers, referred to as “guests,” run on a real computer known as the “host.” Despite sharing the same host, every virtual machine has its own operating system and functions separately from the others. This suggests, for example, that a virtual MacOS machine can be operated by an actual PC.

Virtual machine technologies have many applications in both on-premises and cloud environments. More recently, public cloud services have begun to leverage virtual machines to provide several users with virtual application resources at the same time, making computing even more flexible and economical. Without a doubt, this explains exactly what a virtual machine is.

Why Do We Need Virtual Machines?

A business can use virtual machines (VMs) to run an operating system on a desktop application window that performs similarly to a standalone computer. Virtual machines (VMs) can be configured to test programs in a safe, isolated environment, to meet varied processing power requirements, or to run software that requires a separate operating system.

Virtual machines have long been used in server virtualization, enabling IT teams to pool their computing resources and boost efficiency. Virtual machines can also be used for some operations, such as operating system testing and virus-infected data access, that are considered too risky to be performed in a host environment. Because the virtual machine is segregated from the rest of the system, its software cannot interact with the host. To be very honest, a virtual computer performs this function.

How Do Virtual Computers Operate?

The virtual machine operates on the operating system of the real computer as a process in an application window, just like any other program. Among the crucial files of a virtual machine are its configuration file, log file, virtual disk file, and NVRAM setting file.

Benefits of virtual machines

Compared to physical equipment, virtual machines are easier to maintain and control. 

  • Virtual machines (VMs) save time, money, and physical space by enabling the use of many operating system environments on a single physical computer.
  • By supporting legacy programs, virtual machines (VMs) lower the cost of moving to a new operating system. For instance, a host server running an operating system other than Linux, like Windows, can support a virtual machine running Linux that has a guest Linux distribution loaded on it.
  • Integrated application provisioning and disaster recovery solutions may be offered by virtual machines (VMs).

The drawbacks of virtual machines

  • Virtual machines are better than real machines in a number of respects, but there may also be certain drawbacks:
  • Running many virtual machines on a single physical computer might result in unstable performance if infrastructure requirements are not fulfilled.
  • Virtual computers perform less effectively and more slowly than fully functional actual computers. Most firms blend physical and virtual infrastructure to offset the relative benefits and downsides.

The two types of virtual machines 

Process VMs and system VMs are the two categories of virtual machines from which users can select:

A process virtual machine provides a platform-independent development environment that allows a single process to run as an application on a host computer by concealing the specifics of the underlying hardware or operating system. One example of a process virtual machine (VM) is the Java Virtual Machine, which enables Java programs to run on any operating system as if they were native to that system.

A physical machine can be replaced with a fully virtualized system virtual machine. Multiple virtual machines can share physical resources more easily when a system platform is used. These virtual machines can run independently of the host computer’s operating system. This virtualization process requires a hypervisor, which may run on top of an operating system or bare hardware like VMware ESXi. 

Which five forms of virtualization exist?

With a range of specialized virtualization techniques, it is now feasible to virtualize any aspect of a traditional data center or IT infrastructure.

Hardware virtualization: When virtualizing hardware, separate operating systems and computer systems (VMs) are constructed and integrated into a single main physical server. A hypervisor may communicate directly with a physical server’s CPU and storage capacity to manage the virtual computers. Hardware virtualization, often known as server virtualization, maximizes hardware resources and allows many operating systems to run simultaneously on a single machine.

Software virtualization: A physical host computer can run one or more guest operating systems on a fully functional computer system with hardware by utilizing software virtualization. For example, Android OS may utilize the same hardware to operate natively on a host computer running Microsoft Windows OS. Applications can also be virtualized and sent from a server to the end user’s laptop or smartphone. This makes it possible for employees who work remotely to access centrally hosted programs.

Storage virtualization: Storage may be made to seem like a single unit by virtualizing many physical storage devices into one. Reduced costs, load balancing, and enhanced speed and performance are among the advantages. Storage virtualization also helps with disaster recovery planning by reducing downtime since virtual storage data may be quickly and reliably transferred to a new location.

Network virtualization: Multiple subnetworks can be built on a single physical network by combining equipment into a single software-based virtual network resource. Network virtualization also divides available bandwidth into several channels that may be assigned to servers and other devices quickly. Among the advantages are enhanced security, reliability, speed, and data usage monitoring. Network virtualization is a good choice for businesses where a lot of people need ongoing access.

Desktop virtualization: This widely used type of virtualization allows users to save their desktop environment on a remote server and access it from any device, anywhere. In addition to being easy to use, virtual desktops also provide better data protection, lower costs for software licensing and upgrades, and simpler management.

Container vs. virtual machine.

Similar to Kubernetes, container technology enables separated programs to run on the same platform, making it analogous to virtual machines. While virtual machines virtualize the hardware layer to produce a “computer,” containers package up a single piece of software together with all of its dependencies. Virtual machines are frequently controlled by hypervisors, whereas container systems employ virtual memory hardware to separate the applications and provide shared operating system functionalities from the real host.

One of the key benefits of containers is that they require less overhead than virtual machines. Containers contain only the software, libraries, and other required dependencies. Containers on the same host are much smaller than virtual machines since they use the same operating system kernel. Thus, containers optimize server resources and expedite application delivery and boot time. A few use cases where containers have gained popularity are web applications, microservices, DevOps testing, and increasing the amount of programs that can be deployed per server.

Virtual machines are bigger and require more time to boot up than containers. They offer all the benefits of a completely different operating system, have their own operating system kernel, and are logically isolated from one another. Applications that work on older operating systems, legacy software, and several apps running at once are the ideal candidates to run on virtual machines. It is also possible to employ containers and virtual machines together.