Virtualization administrators can't yet sit on the beach with their laptops all day, but the benefits of server virtualization technology have increased significantly in recent years.
Agile capacity, workload migration, expanded disaster recovery options and better utilization of resources are among the many benefits of server virtualization technology. On the business side, the cost benefits of server virtualization technology include increased productivity and substantial savings from reduced hardware and space requirements.
Here's my short list of the best reasons for mainstream IT environments to go virtual.
1. Virtual machine migration. In my opinion, this is the true enabling attribute of virtualization technology and its greatest single benefit. Its importance will only increase with the introduction of long-distance migration technologies, which move a running virtual machine between data centers that are separated by latent connections. As this emerging technology matures, it will become even more popular.
Migration also includes virtual disk storage, with technologies such as VMware Storage VMotion. This technology has been enhanced with vSphere to include the option of migrating from a fully allocated virtual disk to a thin-provisioned virtual disk. Considering the costs associated with shared storage, the ability to migrate in this fashion has enabled virtualization administrators to provision resources as needed, with no impact to the business.
2. Infrastructure management. Over the years, we've learned that with virtualization technology, abstraction is a good thing. With virtualized servers, data centers are decoupled from hardware that can fail and take a server offline. Sure, XenServer, Hyper-V or ESX hosts can fail, but server virtualization provides a native architecture as well as a rich offering of management tools to keep workloads available. This abstraction can be made to break down barriers once associated with specific server brands, allowing administrators to focus on infrastructure management.
Moreover, there are fewer moving pieces with a virtualized server infrastructure, an abstraction that also extends to storage environments. Migrating to new disk systems in a SAN environment is generally quite easy with virtualized technologies. In some cases, it can be done with zero downtime to the virtual machine. Without assistance from advanced storage virtualization systems, this would be a tremendous task.
There are also virtualization security benefits. These include separating development from production workloads, allocating isolated resources for update testing and, in the case of desktop virtualization, the ability to ensure that data does not leave your data center.
3. Instant capacity. There are fewer finer pleasures than providing a virtual machine almost instantaneously to a requestor. Virtualization enables elastic capacity to provide systems at a moment's notice. In the physical server world, it could take weeks to take a server from "PO to ping." Deployment issues involving cabling, shipping, purchase orders, lab build time and other operational processes are a nightmare to address in comparison to the deployment of a virtualization-enhanced agile data center.
Lab management tools that automatically provision virtual machines for test and development purposes through a managed interface are another example of how virtualization improves productivity and why that productivity is a true driver of the technology.
4. Virtualization cost benefits. The cost-benefit analysis on server purchases that don't return the investment is pretty obvious. With virtualization, data centers can consolidate server requirements to fewer, more powerful systems that use resources more effectively. This extends to space, power, port and cabling savings. These supporting elements of infrastructure can be very expensive, especially with respect to network and storage ports.
5. Isolating applications. In the physical server world, data centers frequently consolidated applications on servers. This was good for keeping the number of physical servers down but led to application incompatibilities or obscure maintenance windows. With virtualization, we can now put applications on dedicated operating systems on a virtual server so that there are no local compatibilities issues. This also allows us to correctly provision a virtual machine for the precise amount of memory and disk access, which are two primary resource areas in virtualization.
There is a downside, however, which is an increase in the number of installed operating systems in the environment. This is a common occurrence once virtualized servers become the standard. That side note aside, isolating applications in their own OS allows internal developers to deploy agile IT services.
ABOUT THE AUTHOR: Rick Vanover (VCP, MCITP, MCSA) is an IT infrastructure
manager for a large financial services organization in Columbus, Ohio. Rick has years of IT
experience and focuses on virtualization, Windows-based server administration and system
This was first published in October 2009