Virtualization is the abstraction of the computer hardware, hiding the physical computer from the way in which it is used. With virtualization a single physical server appears as multiple logical “virtual machines” by using a hypervisor or virtual machine monitor (VMM) software. In this way the virtualized server platform allows multiple operating systems to run on a host computer at the same time with each OS thinking it has control of its own complete server.
Virtualization is the core technology of a scalable IT infrastructure. By decoupling software from hardware and presenting a logical view of physical hardware to software, a single server can act as multiple, independent servers.
By running several virtual machines (VMs) on a single server the hardware can be more efficiently and economically utilized and maintained. Virtualization enables a continuity of Moore’s Law by taking advantage of processing power and creates opportunities for system configurations beyond simple consolidation not possible or prohibitively costly without virtual technologies such as:
- Availability - virtual image recovery and backup systems
- Dynamic Data Center - flexible pools of resources that can be quickly reconfigured
- Virtual Clients - Reduced client costs and increased data security
- Fault Tolerance - Critical applications
- Hardware Independent Scalability - Automated scaling in real time to match user demands
Uses of Virtualization Technology
With virtualization came a lot of opportunities. Being able to use one machine as if it was several has many advantages and applications:
- Virtual Tier Consolidation - The interface, application, and database tiers of a multi-tier software architecture can combine on a physical machine running in virtual machines.
- Application Scaling using Virtualization - Increasing and decreasing virtualized resources as application needs grow or recede.
- Application Consolidation using Virtualization - Application consolidation solutions help improve application integration by consolidating multiple applications. Application instances on a single server eliminate redundancies, increase performance, reduce maintenance costs, and reduce the cost, time and risks associated with application upgrades. By allowing applications to share the same virtualized infrastructure, enterprises can realize hardware utilization rates approaching 100 percent instead of the typical 15 percent on a standalone machine. Application consolidation using virtualization is highly recommended when you have a multiple applications which are using low system resources.
In use since the 1960s there is new attention on virtualization due to recent development of new virtualization platforms and technologies. Where the primary use of virtualization has been in capital expenditure reduction, the newest technologies from Intel and its partners now create greater possibilities for virtualization to reduce operational expenditures.