Microsoft Lync Server 2010 : Virtualization Overview (part 2) - Benefits of Virtualization, Virtualization Vendors

3. Benefits of Virtualization

It should be apparent from the previous few pages that virtualization offers companies a new level of flexibility in server deployment and management not possible with using only physical hardware. This section covers some of the benefits that organizations can realize from hardware virtualization, including the following:

• Fewer physical servers—By virtualizing servers, an organization requires fewer physical servers. Because new servers now support nearly 100 GB of RAM at an affordable price point, companies can increase their consolidation ratios by placing more and more virtual machines on the same physical hardware.

• Infrastructure flexibility—As physical servers begin to demand additional hardware upgrades, the traditional model required organizations to purchase more memory or processing power. In a virtual environment, administrators can easily shut down a virtual machine and add more memory or processors. Some products even allow this to happen without shutting down the virtual machine. Additionally, expanding the infrastructure to accommodate new virtual machines can become a simple matter of adding a new physical host to the cluster. This adds an entirely new level of flexibility to managing server resources.

• Increased availability—In physical environments, servers were often built to be as redundant as possible with multiple hard drives and power supplies. These additional expenses are still useful for a host server, but do not apply to virtual machines. As long as a virtual machine is made highly available, it can be easily restarted on a different host if a physical host fails. It is still best practice to design the hosts to be fault tolerant, but the additional expense of designing every single server for hardware redundancy becomes unnecessary. Organizations can achieve a higher level of service and availability for servers by abstracting the hardware layer through virtualization.

• Reduced operating expenses—By reducing the number of physical servers in the environment, organizations can also realize decreased operating expenses associated with physical servers. Fees for rack space, cooling, and power are reduced when fewer physical servers are used.

• Application isolation—A significant challenge in the days of using physical servers for everything was that each new server required its own physical hardware. Typically, this was difficult because of the additional expense involved to purchase and install a new server. To work around budget issues, administrators began to collocate different applications on the same physical server, but because application vendors usually test and expect their application to have its own dedicated environment, this caused performance or configuration issues that were difficult to troubleshoot. With virtualization, each application can have its own dedicated server due to how easy it is to create virtual machines.

• Legacy application support—An unfortunate reality for many organizations is a need to support legacy applications that run on only legacy operating systems. As the hardware these systems run on begins to fail or needs replacement, organizations must either deploy these applications on new hardware or operating systems not certified for the product. Using virtualization, companies can create a new virtual machine running a legacy operating system very easily. They can also perform a physical-to-virtual (P2V) migration of the existing physical server to transform it as-is to a virtual machine.