Server virtualization services creates a representative form of the actual object that remains closest to the description. It distinguishes the resource or service request from the underlying physical delivery of the actual service. In computing terminology, it is basically a framework or an architecture that allows the end user to avail maximum usage of computer resources accessible. It allows running multiple instances of Operating systems and Applications on a single Computer where each of the operating systems runs as a self-contained machine called “Virtual Machine”.
Virtual Machine Monitor-VMM, the software layer is installed either over the host Operating System or directly onto the system hardware. The way VMM is installed determines the Virtualization Architecture the Server is dependent on. It enables switching between Virtual Machines without rebooting or hardware partitioning.
Hosted Architecture: A base OS is first installed on the system and it is upon this OS that the software layer VMM is installed to allow users to run guest OS. The communication with I/O devices is majorly controlled by the host OS with limited access to the guest OS for just a few I/o devices.
Bare-Metal Architecture: The software layer VMM is directly installed on system hardware thus allowing direct access between I/o devices and VMM. This improves I/O performance with real-time OS support
Types of Virtualization
It refers to utilizing a segment of a single physical network through a logical segmentation. They are deployed as logical services. It encapsulates the hardware and software network resources and functionality into a single virtual network. Each segment is independent of the other and can be assigned in real time for scaling of networks for business needs can be achieved by adding partitions.
VDI stands for Virtual Desktop Infrastructure popularized by VMWare. VM has all the OS, applications, Software’s been installed and is managed in one single place or in a hosted environment and then access to this system is remotely given to the end-user. End-user thus uses all the necessary applications remotely without the need of installing on his local computer. As the number of users grows in an organization, provision of remote access can be given thus IT Desktop support process becomes much easier.
A physical server is partitioned into multiple smaller virtual servers each having the capability to behave like an actual server with the resources of host server are masked from the user. Each virtual server can run and reboot its own OS independent from that on the other virtual server. The reduced hardware cost and increased resource utilization encourage choosing this option.