A virtual machine can NEVER be as good as a physical machine, especially where I/O's are concern. Symantec always recommends a physical machine as a physical server. You ae using dedup which places heavy demands on both CPU as well as I/O's, so it would not be wise to use a VM as a media server.
When you use a VM as a media server, you are using an alternative configuration which means that if you cannot reproduce the problem with a physical machine, then Symantec will not support it. This will make any trouble-shooting difficult.
The definition of an Alternative configuration from Symantec's Techncial Support Policy (which is publicly available) is:
Alternative Configurations: Our Licensed Software is designed to interoperate with many types of systems, applications, and hardware. Sometimes a customer may choose to use our Licensed Software in an Alternative Configuration, namely, an environment that has not been validated, approved or verified to operate with our Licensed Software or which does not support such Licensed Software or only supports limited functionality. In most cases, we do not support Alternative Configurations, and we have no obligation to provide Support Services to Licensed Software in an Alternative Configuration. Symantec makes no warranty with respect to use of Licensed Software in an Alternative Configuration and any such use is at your own risk. A “Supported Configuration” might be converted into an “Alternative Configuration” where a vendor modifies one of its components that is part of the original “Supported Configuration.” As a consequence, your Licensed Software would then be operating in an Alternative Configuration. If you experience a Problem with the Licensed Software in an Alternative Configuration or if your issue deals with script that was not developed by Symantec or an authorized consulting partner, then we may ask you to reproduce the Problem in a Supported Configuration environment. Please note we have no obligation to attempt to resolve Problems that cannot be replicated in a Supported Configuration. However, if the Problem can be replicated in a “Supported Configuration,” we will investigate the Problem in that Supported Configuration and attempt to resolve it. If the Problem cannot be replicated in a Supported Configuration, then we may elect not to work on that Problem.
