Virtual server

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A virtual server is a virtual machine (VM) that is running on top of a physical server. The physical server containing the virtual server is commonly called the host whereas each virtual server contained in the host is referred to as a guest. A virtual server is created through hardware virtualization.

Virtual servers are isolated in their own virtual environment allowing multiple instances to be hosted simultaneously on a single server. Guests on the server can run different applications or tasks, on different operating systems, independently from one another. To ensure independence and consistency, the physical server utilizes a hypervisor whose role is to monitor the states of each guest. To server users, this appears as if each virtual server is a unique physical device thus maximizing the resources and processing-power of a single physical server. Downtime during server maintenance is also minimized since virtual servers can easily be transferred or migrated from one physical server to another given that both servers are running on the same processor manufacturers.