Choose a Virtualization Vendor for Mac OS X Servers
There are three major companies that make virtualization software for Macs: Parallels, VMware, and Oracle. If you plan to run Lion Server in a virtualized environment, you will need to select one of these products to do so. In a nutshell, here are the choices:
Parallels Server: Meant for serious virtualization of multiple production servers on one Mac, Parallels Server includes management software for the servers. It comes in several versions, from a $300 Mac mini edition to the $2,000 Parallels Server for Mac.
VMware Fusion: Another user-level virtualization package, Fusion is very similar to Parallels Desktop and similarly priced. You need version 4 or later to run Lion in a virtual machine.
Oracle VirtualBox: This open source product is free for personal use.
You can use the desktop versions for testing servers or for running services that don’t use a lot of system resources. A desktop version won’t let you assign as much of the Mac hardware to a virtual machine Parallels Server.