Virtualization is one of the hottest trends in IT, and for good reason. Virtualization can help save your organization plenty of money, as well as reduce your overall ongoing staffing, support and maintenance needs.

Still, virtualization isn't a universal remedy. There are several things virtualization can't do for your organization, and understanding the limitations of virtualization is as important as understanding the benefits.

Here are some of the biggest virtualization myths:

1.    Virtual machines have higher availablility and reliability. This is one of the "features" of virtualization that vendors often talk about. They point out how applications can easily be restarted during an outage, for example. Unfortunately, virtualization also creates a single point of failure in the one physical machine. Complement your virtualization with orchestration management, however, and you can actually wind up increasing both availability and reliability.

2.    Virtualization will allow applications to perform exactly as they did before. The fact of the matter is that performance is likely to degrade. The degree to which it degrades depends on the physical hardware of the server, as well as the rest of the server environment. In many cases, the degredation will be so small as to be irrelevant, however.

3.    Virtualization always saves money. To be sure, most virtualization implementations will reduce the total cost of ownership. However, it's important to recognize that some of the potential savings have to do with staffing levels. If you virtualize a great deal of your environment but still wind up having to staff the same number of admins or engineers, or if you're not willing to downsize some, you're going to wind up paying more in the long run.

4.    Virtualization is important for SOA. Some SOA applications do provide good prospects for virtual machines. The application services can be encapsulated, and then hosted on as many machines as the organzation needs. Still, there are many other factors as to whether virtualization will perform for SOA, including communications architecture, application design and host configuration.

5.    Virtualization is more secure. In some ways, virtualization makes security resposne more effecient. If a single virtual machine is breached, then that machine can be stopped and reloaded without impacting other virtual machines. Still, the virtual machine technological layer may or may not be secure in and of itself, and virtual machines that have been compromised could have also corrupted shared data.

6.    Any organization can be ready for virtualization. There are many issues that have to be addressed before virtualization can be considered, such as managment team issues, development  issues and process issues. This is to say nothing of the potential human impact of virtualization, and the political fallout it could cause in a larger environment. A rush to virtualize can cause catastrophic damage in other areas.

7.    Virtualization doesn't require specialized knowledge. Regardless of what proponents might say, adding an entirely new layer of software and migrating applicaitons from individual servers to a single larger machine takes some knowledge, both in terms of the virtualization technology and in the application area.