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Server Virtualization

Server Virtualization essentially means that the operating system is separated from the server hardware; several virtual machines can be created on the same server, which can only use a pre-defined quantity of hardware resources and different independent operating systems may run on them.

In a virtualized server infrastructure, a hypervisor software runs on physical machines to implement virtual machinery operation.

In an Intel environment, the most widespread software products to provide hypervisor functionality are Microsoft Hyper-V and VMWare ESXi.


Why is it resonable to virtualize servers?

The original and primary objective of virtual technology was to increase the resource utilization of servers. If traditional physical servers are applied, the increase of utilization is limited by two factors:

  • processor supply enables a calculation capacity even at a basic level which cannot be continuously exploited by applications (software) for the most part. Servers must be dimensioned for maximum loads, which automatically entails the waste of resources during periods of low utilization rates,
  • theoretically, processor utilization could be increased by concentrating several applications to a single physical server; however, this is restricted by the memory management problems of operating systems and applications. Typically, applications to execute newer and newer functions entail the installation of new servers, posing a major challenge to machine room infrastructure by ever increasing power supply, cooling and space demands.

However, server virtualization can be used for creating several virtual computers on a single physical machine, which continue to ensure a completely individual and independent environment for applications in addition to increasing processor utilization. As a result, the number of servers required, power demands, cooling demands - that is, operating costs - will decrease.

Hypervisor software applications facilitate the improvement of IT services standards in addition to increasing server resource utilization. Actually, they enable the movement of virtual computers among various physical machines (thereby realizing fault tolerance) and the dynamic reallocation of the resources assigned to the machines as required.

Virtualization technology is a basic pre-requisite for setting up an infrastructure of discretional capacity and service content which are characteristic of cloud services.


Is it worth applying a server virtualization technology?

In terms of costs, the consolidation of a few old servers to a new server may be a development with a short period of return.

It is also important to remember, however, that server virtualization increases the impact of a potential breakdown; therefore it is worth putting suitable IT continuitymeasures in place simultaneously with the virtualization development.

The implementation of higher-level virtualization services can also be subject to individual pre-requisites (such as the use of a central storage system, redundant network infrastructure) which are difficult to typify, so please ask for our advice in such cases.


Based on a survey of Your current environment, G-DAS experts undertake to produce a technical and financial analysis on the feasibility of virtualization.