Although we focus primarily on VMware® Virtualization and Hypervisor technologies and products, we also remain open to other alternative hardware and software virtualization and virtual machine solutions that exist, or are entering, the market. Some of these VMware alternatives offer exciting opportunities for using Open Source Software (OSS) solutions to VM technology too. Ultimately the decision is yours to make, though depending on your choice, we may not be able to pre-install your chosen hypervisor and/or VM software for you.
Regardless of your chosen computing hypervisor (aka virtual machine monitor), your goal remains the same: implementing a virtualization platform that allows multiple operating systems to run on your host computer at the same time. The primary considerations beyond may include:
- Type: "bare metal" or "hosted" virtual machine software.
- Supported Operating Systems : probably the most important factor in deciding which Virtualization solution meets your needs. E.g., will you need Windows Server 2003 or 2008 support, Windows desktop operating systems (i.e., Windows XP, Windows Vista), Linux support (perhaps Ubuntu 8.10, openSUSE 11.1, or Fedora Core 11), or even Apple OSX support?
- Supported Hardware : also very important for obvious reasons.
- Capacities : e.g., what is the maximum number of simultaneous Virtual Machines you can run effectively, how much System RAM can the Hypervisor use, etc.?
- Efficiency : for the same hardware resources, which Virtualization technology provides the best performance-per-buck?
- Portability / Interoperability / Conversion : all worth thinking about.
The following sections mention a few VMware alternatives that either well known, or are rising in popularity.
These open source alternatives to VMware are less full-featured than their VMware counterparts, but may fit your needs, and VirtualBox is rather popular currently. xVM Virtual Server is currently in pre-release state (as of November, 2008), though it looks promising in early Beta releases.
VirtualBox provides x86 virtualization software that targets the enterprise as well as home use. Although VirtualBox tends to fall short in various side-by-side reviews against VMware Workstation, it is actively developed and has rather decent feature set while being the a professional solution that is freely available as Open Source Software under the terms of the GNU General Public License (GPL).
VirtualBox currently runs on Windows, Linux, Macintosh and OpenSolaris hosts and supports guest operating systems including Windows (NT 4.0, 2000, XP, Server 2003, Vista), DOS/Windows 3.x, Linux (2.4 and 2.6), Solaris and OpenSolaris, OpenBSD, and other operating systems.
2008-12-17: VirtualBox 2.1.0 was just released. Sun's VirtualBox 2.1.0 is a major update with some significant new features that make VirtualBox a bit more competitive,
though it is still certainly trailing VMware Workstation 6.5 considerably. The welcome new features in VirtualBox 2.1 include better 64-bit support, hardware virtualization on the Mac,
3D acceleration ("experimental" yet), easier networking on Windows and Linux, plus full VMDK/VHD support including snapshots. See the VirtualBox 2.1 Release Notes / ChangeLog for a more information and list of changes.
Xen is another open source alternatives to VMware. The Xen® hypervisor attempts to offer a powerful, efficient, and secure feature set for virtualization of x86, x86_64, IA64, PowerPC, and other CPU architectures. It currently supports a range of guest operating systems including Windows®, Linux®, Solaris®, and BSD operating systems.
With Xen virtualization, a thin software layer known as the Xen hypervisor is inserted between the server's hardware and the operating system. This abstraction layer allows each physical server to run one or more virtual servers. Xen uses a paravirtualization technology that is designed to be both fast and secure and offers near-native performance for virtual servers with less overhead than some competing virtualization software.
If you are a pure-Microsoft site with a nearly all-Microsoft Server-Products infrastructure, perhaps you should consider this solution.
Other Hypervisors
