Server virtualization is a business strategy that is here to stay and that offers many considerable organizational benefits. You can consolidate application workloads that are running on underutilized servers which can result in reductions in hardware costs, energy and infrastructure costs, and space requirements. Additionally, server virtualization can also increase the availability and reliability of applications, improve disaster recovery efforts, and streamline data backup.
Realizing these server virtualization benefits does require some effort. These fantastic benefits are not automatic, despite all the hype surrounding server virtualization. They require a skillset that may be new to some organizations, and thus planning needs to be taken seriously and with forethought. Server virtualization, in fact, may not be a good fit for your organization and so when possible, a consultant that has experience in virtual server deployment and a strong virtualization methodology should be used.
Server virtualization works best for applications that utilize less than half of a servers capacity or resources. Larger, transactional database applications are typically not a good fit for server virtualization.
Given the fact that most servers are grossly underutilized, there is a huge waste of IT resources likely at any organization. Virtualization uses a hypervisor, which is software that transparently allocates server resources and manages resource conflict. This, in turn, allows multiple applications to share the same physical server increasing the utilization of the machine. While simple in theory, there are challenges that come with server virtualization.
Workload capacity and performance planning
When you suddenly increase the utilization of an underutilized server, you automatically create the need to better manage that servers performance. Depending on the application being run on the server, this increased utilization could cause problems.
Operational processes and procedures
Like the first challenge, the sudden increase in server utilization may require your organization to redefine internal processes for monitoring performance, and possibly the tools used to monitor server diagnostics.
System architecture and design
Youll need to determine (before your server virtualization effort) how virtualization will affect overall budget, system component selection, how much CPU, storage capacity, and network bandwidth youll need so that your effort runs smoothly.
Storage allocation and management
Youll need to consider application transaction rates and capacity usage so that you allocate the appropriate amount of storage space. If not, youll run the risk of exceeding available capacity and constraining your application performance.
Security vulnerabilities are amplified in a virtual server environment, so be sure to address security patching and access control.
While these challenges are not tiny, they are very manageable provided theyre addressed prior to server virtualization. Consult with a server virtualization expert to help you get it right.