Server computers – machines that store files and applications of computer networks – have to be very powerful. Some contain central processing units (CPU), consisting in turn of multiple processors, allowing them to easily perform complex tasks. Administrators of computer servers usually assign a separate server for a specific application or a specific task. Many problems cannot be well carried out jointly with others – each needs its own dedicated machine. Organization system of “one application – one server” also makes it easier to find the source of problems, if any. This approach, from a technical point of view is a simple way of ordering a computer network.
But this way of rationalizing raises a number of problems. One of them is that you do not use the full computing power of today’s server computers. Most dedicated servers use only a small fraction of their potential for information processing. Another problem is the need to allocate significant physical space to accommodate servers with increasing and more complex computer network. Ultimately, the data center can be crowded rack, basking and consuming large amounts of electricity.
Server virtualization is an attempt to simultaneously solve these two problems. Under the proposed method, an administrator, using special software that can convert a physical server into multiple virtual machines. Each virtual server acts as a separate physical device with its operating system (OS). Theoretically, you can create a sufficient number of virtual servers to use all the computing power of the machine, but in practice this approach is not always justified.
The concept of virtualization is not new. Computer scientists for decades have been creating virtual machines to supercomputers. However, only in recent years, the opportunity to implement server virtualization has came up. In a world of information technology (IT) server virtualization is a hot topic. This is still a new technology and several companies offer different approaches to its implementation.