After years of vendor hype about virtualization, customers are realizing real-life business and IT benefits from implementing this technology. By moving away from the traditional ‘silo’ approach of linking applications to a specific IT infrastructure towards an approach that creates shared pools of virtualized server, storage and network resources, customers can dynamically assign the pooled resources wherever and whenever needed. Although many vendors have focused their selling and marketing efforts on the virtualization benefits for enterprise-class customers, more and more SMB customers are reaping virtualization rewards as well.
Virtualization’s benefits of increased utilization, improved service reliability and the positive impact on both internal and external business processes apply to SMB as well as to enterprise-class operations. The products of companies offering virtualization deployment services, particularly in server virtualization, logically ‘break’ each physical server into several independent virtual servers, allowing customers to run multiple operating systems and applications on a single machine simultaneously. Each virtual server is independent of the others, so failure in one will not affect others. Furthermore, the workload from the failed virtual server can be reassigned to another virtual machine. In a 2007 IDC survey of 19 North American-based IT organizations, 80% of the companies reported adding virtual machines to their systems management portfolios.
Some of the benefits of virtualization are:
- Lower number of physical servers – one can reduce hardware maintenance costs because of a lower number of physical servers
- By implementing a server consolidation strategy, one can increase the space utilization efficiency in their data center.
- By having each application within its own "virtual server", one can prevent one application from impacting another application when upgrades or changes are made.
- One can develop a standard virtual server build that can be easily duplicated which will speed up server deployment.
- One can deploy multiple operating system technologies on a single hardware platform (i.e. Windows Server 2003, Linux, Windows 2000, etc).
- When running in a virtual machine, an operating system can’t tell whether it is running on a virtual machine or a physical server, nor can applications or other computers on a network. Nevertheless, a virtual machine is composed entirely of software and contains no hardware components whatsoever.
- Virtual machines are compatible with Sun x64 servers powered by AMD Opteron and Intel Xeon processors.
Isolation
Virtual machines are isolated from each other as if physically separated.
Encapsulation
Virtual machines encapsulate a complete computing environment.
Hardware Independence
Virtual machines run independently of underlying hardware.
When IT organizations virtualize the hardware, they empower themselves to make more flexible, dynamic choices in their application deployment and their allocation of resources – business benefits that affect the bottom line- including higher server utilization, improved service levels, ability to better meet changing business requirements, increased business continuity and disaster recovery
Through the use of virtualization technology, the days of bringing applications down because of scheduled server maintenance are over. Instead, IT organizations use virtualization to migrate running applications from a server they wish to take down to a backup server. With all applications moved off a server without disruption, it can be maintained or even replaced without any impact on service delivery.
Freedom From Vendor-Imposed Upgrade Cycles
Some solutions virtualize the hardware itself, including the processor, memory, disk and I/O resources. Because the hardware that the operating system sees is virtual and not physical, the OS and the software installed on it can be moved from server to server without concern for the underlying platform – freeing IT organizations from vendor-imposed hardware and software upgrade cycles.
Virtual Hardware To Support Legacy Operating Systems
IT organizations can migrate entire environments from physical servers whose service plans have expired to virtual machines running on state-of-the-art Sun x64 servers. This helps address performance and space, power and cooling concerns by supporting multiple such environments per server.
Dynamic Resource Sharing
Because some solutions virtualize disk drives as flat files, these files can be moved from server to server to optimize utilization levels and to manage service levels. Resource allocation can be used to manage complimentary applications on the same server. For example, it could be configured to favor a busy On-Line Transaction Processing (OLTP) database during the day, while favoring long-running data warehousing operations at night. For even more dynamic resource management, virtualization technology can dynamically migrate running environments between servers, giving IT organizations the ability to respond to workload fluctuations in real time.
Security and Fault Isolation
Virtualizing at the hardware level encapsulates each guest operating system in its own virtual machine, containing faults to a single environment. This helps increase reliability by limiting the propagation of faults and allowing them to be handled by software, rather than hardware mechanisms. Likewise, because each virtual machine isolates its guest operating system and applications, any security flaw affecting one environment does not affect another.
Business Continuity and backups
With operating systems and applications encapsulated into disk files, they can be backed up as a complete unit and they can be migrated to a secondary datacenter, ready to activate in the event of a failure at the primary location.