Virtualization is a method of running multiple independent virtual operating systems on a single physical computer. It is a way of maximizing physical resources to maximize the investment in hardware.
Virtualization is best described by using an example. Let’s take a business that has 5 physical servers, such as Mail, Database, ERP, File / Print and a Terminal Server. The physical servers can be running a mixture of operating systems such as Windows 2008 R2, Windows 2008 and Windows 2003.
Maintaining this environment will consist of maintaining the 5 physical server platforms, operating systems and applications.
Each physical server typically runs at only a fraction of its capacity. Typical CPU utilization of 10%
or less make the physical servers extremely inefficient.
If this business was to virtualize then only one physical server is required, referred to as a host.
The 5 servers that were running previously will all run on the host in their own virtual environment, referred to as Virtual Machines.
The Virtual Machines can be allocated resources to meet demand, such as CPU, Memory, Network and Storage.
Virtualization provides business with the following benefits:
- Reduce costs By consolidation all the physical servers into virtual machines business save greatly on hardware and support costs
- Increase efficiency Better utilization of the hardware on a physical server with increase efficiency
- Improve business continuity One of the big advantages of virtualization is the portability of the virtualized machines. Business can build redundant data centres by replicating the virtual machines to another site.
- Business agility Virtualization enable business the ability to adapt rapidly to changes in the business environment.
- Disaster Recovery Virtualization greatly improves disaster recovery. In the event of a failure a virtual machine can be restored in a few hours compared to a day for a complete physical server restore.
Virtual machines can be easily moved between hosts.