VMware is a software company that specializes in desktop and server virtualization. The most popular VMWare products are VMWare workstation (a desktop based virtualization software) and ESX Server (a server virtualization product.) ESX server is part of the Virtual Infrastructure 3 suite of enterprise virtualization products. For those who do not want to pay for an enterprise license before becoming more educated in virtualization, or who want to tinker with virtualization as a hobby (without incurring a cost,) VMWare server is the perfect option.
VMWare Server is the free virtualization product for Windows and Linux servers. You can download VMWare Server for free at http://www.vmware.com/download/server/. Note that Windows Server (and the accompanying license) is required to run VMWare Server on top of a Windows platform, while just about any distribution of Linux counts as a 'server' and can run VMWare server on top without licensing issues. VMWare Server allows companies to partition a physical server into multiple virtual machines to start experiencing the benefits of virtualization. Hobbyists can also accomplish the same on a reasonably powered desktop.
With the introduction out of the way, lets talk about what you can actually do with VMWare Server. Most IT departments have servers in production that are very under-utilized. Print servers, many web servers, one-off application servers and even some file servers are on physical hardware that is capable of running much more demanding applications. VMWare Server allows you to turn many of these physical servers into virtual machines that reside on one physical server. This will better utilize the resources of the single physical server. This also has the net effect of reducing the amount of hardware that a data center needs. Less hardware means less electricity for power and cooling. It's a win:win situation for IT.
For the hobbyist, VMWare server allows a person to tinker with other operating systems while maintaining a favorite OS to work on. On my personal desktop, for instance, I run Ubuntu 7.10 x64 as my main OS. The machine has a dual-core 3.0 GHz 64 bit AMD processor, 4 GB of RAM and an array of hard drives. Because I want to be able to use all 4GB of RAM, I chose to use the 64 bit version of Ubuntu. There are a multitude of Windows applications that I need to use on a daily basis while consulting for clients who run the Microsoft Windows platform. I use VMWare server to run several virtual machines (VMs) with Server 2003/2008, Exchange Server 2003/2007, SQL Server 2005, Terminal Server, SharePoint Server 2007, IIS, SCOM, etc. Without VMWare Server, I would need to have many individual PCs on my network imitating the various server operating systems and enterprise applications. Now, I can deploy, run, test, break, fix, etc., any of these operating systems and enterprise applications on a single machine. The best part is that I can do all of this without modifying the underlying base operating system on my machine. I can also save the VMs in various states for further testing or to archive for another project.
Hopefully, by now you can see how great of a technology virtualization is. VMWare server will allow you to test and tinker with this technology without modifying your main operating system and without a cost. If you want more information on virtualization or VMWare, leave a comment and I will answer your questions in new posts on this blog. You can also email me directly with questions. My email address is in the 'About Me' section on the main page.