Virtual Machine
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Virtual machine What is virtual machine? And how it works?
A virtual machine is a completely isolated guest operating system installation within a normal host operating system. Modern virtual machines are implemented with either software emulation or hardware virtualization or both together, so using virtual machine we can install another operating system works in the same computer and located in the same hard disk, meaning that one operating system works inside another one. That is the idea of virtual machine. A virtual machine is a software implementation of a machine that executes programs like a physical machine. Virtual machines are separated into two major categories, based on their use and degree of correspondence to any real machine. A system virtual machine provides a complete system platform which supports the execution of a complete operating system. The virtual machine typically emulates a physical computing environment, but requests for CPU, memory, hard disk, network and other hardware resources are managed by a virtualization layer which translates these requests to the underlying physical hardware. VMs are created within a virtualization layer, such as a hypervisor or a virtualization platform that runs on top of a client or server operating system. This operating system is known as the host OS. The virtualization layer can be used to create many individual, isolated VM environments. Typically, guest operating systems and programs are not aware that they are running on a virtual platform and, as long as the VM's virtual platform is supported, this software can be installed in the same way it would be deployed to physical server hardware. For example, the guest OS might appear to have a physical hard disk attached to it, but actual I/O requests are translated by the virtualization layer so they actually occur against a file that is accessible by the host OS. Virtual machines can provide numerous advantages over the installation of OS's and software directly on physical hardware. Isolation ensures that applications and services that run within a VM cannot interfere with the host OS or other VMs. VMs can also be easily moved,
copied, and reassigned between host servers to optimize hardware resource utilization. Administrators can also take advantage of virtual environments to simply backups, disaster recovery, new deployments and basic system administration tasks. The use of virtual machines also comes with several important management considerations, many of which can be addressed through general systems administration best practices and tools that are designed to manage VMs.
A virtual machine is a completely isolated guest operating system installation within a normal host operating system. Modern virtual machines are implemented with either software emulation or hardware virtualization or both together, so using virtual machine we can install another operating system works in the same computer and located in the same hard disk, meaning that one operating system works inside another one. That is the idea of virtual machine. A virtual machine is a software implementation of a machine that executes programs like a physical machine. Virtual machines are separated into two major categories, based on their use and degree of correspondence to any real machine. A system virtual machine provides a complete system platform which supports the execution of a complete operating system. The virtual machine typically emulates a physical computing environment, but requests for CPU, memory, hard disk, network and other hardware resources are managed by a virtualization layer which translates these requests to the underlying physical hardware. VMs are created within a virtualization layer, such as a hypervisor or a virtualization platform that runs on top of a client or server operating system. This operating system is known as the host OS. The virtualization layer can be used to create many individual, isolated VM environments. Typically, guest operating systems and programs are not aware that they are running on a virtual platform and, as long as the VM's virtual platform is supported, this software can be installed in the same way it would be deployed to physical server hardware. For example, the guest OS might appear to have a physical hard disk attached to it, but actual I/O requests are translated by the virtualization layer so they actually occur against a file that is accessible by the host OS. Virtual machines can provide numerous advantages over the installation of OS's and software directly on physical hardware. Isolation ensures that applications and services that run within a VM cannot interfere with the host OS or other VMs. VMs can also be easily moved,
copied, and reassigned between host servers to optimize hardware resource utilization. Administrators can also take advantage of virtual environments to simply backups, disaster recovery, new deployments and basic system administration tasks. The use of virtual machines also comes with several important management considerations, many of which can be addressed through general systems administration best practices and tools that are designed to manage VMs.
