2 types of VMs currently available:

VMs are often classified by supervisors or by the nature of the work the VM is used to support. Additionally, they are further divided into two types as follows:

1. Process VMs:A process VM is a temporary, platform-independent programming environment for executing a single process as an application. The environment provides a high level of abstraction, hiding the underlying hardware or operating system. A process VM is created when a process begins and destroyed when the process ends. Two common examples of process virtual machines are the Java Virtual Machine, which is part of the Java platform, and the Common Language Runtime, used for the .NET Framework.

   System Virtual Machines (System VMs): A System Virtual Machine is a fully virtualized environment hosted on a physical server and running its own operating system. VMs share the physical resources of the host server but provide a complete environment for running applications and services, just like a physical machine, but without the overhead. System Virtual Machines rely on a hypervisor to virtualize hardware resources and provide the virtual machine environment. Common examples of system virtual machines include those supported by virtualization platforms such as VMware vSphere and Microsoft Hyper-V.

   
   

   What’s the difference between a VM and a container?

   
   

   Containers are similar to virtual machines, except they only virtualize the operating system, not the underlying hardware.Containers include code, system tools, runtime, system libraries, and the settings necessary to run the applications contained within the container. That’s why containers are often used for multiple applications running on the same operating system. Containers are also used for native applications, cloud-distributed applications, and to package legacy applications to increase portability and deployment simplicity. Docker, which entered the market in 2013 as a Linux-based container platform, is one of the leading container developers.

   Although containers are less expensive than VMs and much lighter, they also start up faster, use fewer server resources, and are more portable, making them very suitable for modern application technologies like microservices, but all containers running on the same server or moved to a different server must support the same operating system. In contrast, Virtual Machines can run different operating systems and they offer a higher degree of isolation; although, they can be configured to communicate with each other when needed. Therefore, Virtual Machines are better suited for monolithic applications or for running multiple applications together. They are also useful for legacy applications that require an isolated environment.

   Virtual machines take up more space than containers because they need a guest operating system to run. Each container shares the host’s operating system. Some users deploy containers within virtual machines to improve container security.
   Containers and virtual machines can be used together to complement each other and create the most optimal environment for users. While this increases costs, it provides an additional layer of security that containers alone lack. This combination also helps deploy infrastructure that can support both modern and traditional workloads.

   Setting up a virtual machine

   The process used to set up a virtual machine depends on the virtualization platform. Many platforms offer wizards and other features that make it easy to create and deploy virtual machines. For example, in VMware vSphere, administrators can create a virtual machine from a template or replica, or create a single virtual machine from scratch. Included with vSphere is the New Virtual Machine wizard, which guides users through the process of creating a virtual machine, whether it’s a new virtual machine or one based on a template or replica. In contrast, Red Hat Virtualization takes a different approach to setting up a virtual machine. For example, to install a Linux virtual machine, the user would perform the following steps:

   1. Create an empty virtual machine.

   3. Add a virtual disk for storage.

   5. Add a network interface to connect the virtual machine to the network.

   7. Install the guest operating system.

   9. Register the VM with the Content Delivery Network and attach the necessary registrations.

   11. Install any required guest agents or drivers.

   12. Manage the virtual machine.

       Use the virtual machine that comes with a Several key management considerations are important, and many issues can be resolved through common system administration best practices and tools designed for virtual machine management.
       There are several risks to merging, including exceeding resources or potentially experiencing failures across multiple virtual machines due to physical hardware failures. While businesses can save more money when virtual machines share the same hardware platform, the risks also increase accordingly. Users can place hundreds of virtual machines on the same hardware, but if the hardware platform fails, it could take down dozens or hundreds of virtual machines. However, using virtual machine backups or snapshots can help mitigate those risks.