Virtualization smackdown: Sun xVM VirtualBox 1.6 vs. VMWare Server 2.0 Beta 2

Virtualization smackdown: Sun xVM VirtualBox 1.6 vs. VMWare Server 2.0 Beta 2

Summary: Once strictly the domain of software developers and QA engineers, personal and small-business virtualization products are now becoming an attractive solution for entry-level systems consolidation and foreign OS compatibility applications.


Once strictly the domain of software developers and QA engineers, personal and small-business virtualization products are now becoming an attractive solution for entry-level systems consolidation and foreign OS compatibility applications. These solutions run on host operating systems which do not require the overhead or usual high entry cost of professional hypervisor-based solutions, such as VMWare ESX Server, Microsoft Hyper-V, Virtual Iron, Citrix XenServer, Red Hat Enterprise Linux, SUSE Linux Enterprise Server, Oracle VM and Sun xVM Server, all of which with the exception of the first two are based on the open source Xen hypervisor.

The market leader in this SMB/Personal virtualization space has traditionally been VMWare, which released the very first commercial x86 desktop virtualization product, Workstation 1.0, in 1999. Version 6 of Workstation, which features a portable virtualization "engine" that is used in all of VMWare's host-based virtualization products, was released in late 2007, followed soon VMWare Fusion, a Macintosh version of Workstation. In 2006 VMWare released VMWare Player, a runtime distributable version which permitted any user on a Windows or Linux platform to run self-contained "virtual appliances" created in VMWare GSX Server, VMWare Workstation, or ESX Server. In 2006 VMWare also released Server 1.0 , a free version of its legacy VMWare GSX Server product, which used to be sold for approximately $1000 a copy.

The free personal/SMB virtualization landscape became further complicated with Microsoft's acquisition of Connectix Virtual PC, which later formed the basis of Microsoft's free Virtual Server product. In late 2007, SWSoft, the creators of the Virtuozzo enterprise container virtualization product, purchased Parallels, another independent virtualization product, and shortly after renamed the merged company as Parallels. This was soon followed in February 2008 by Sun Microsystems' purchase of Innotek, the creators of the VirtualBox host-based virtualization solution, in order to help fill out its xVM product line.

Also See: Sun xVM 1.6 VirtualBox and VMWare Server 2.0 Gallery

On May 2nd of 2008 during its CommunityOne event, and concurrent with the initial release of OpenSolaris 2008.05, Sun released version 1.6 of xVM VirtualBox as a free download, and in late March of 2008 VMWare released the second beta of VMWare Server 2.0. As both of these products are free and are addressing a similar market, we thought it would be a good idea to check both of them out and see how they stack up against each other.

Sun xVM VirtualBox 1.6

xVM VirtualBox has the clear advantage of being the only free personal/SMB virtualization product that runs on all the major computing platforms - Windows, Linux, Mac, and Solaris. This is due to the fact that many of its components are written in a cross-platform GUI development library, Nokia/Trolltech's Qt, which is best known for its use in the KDE Linux desktop and the Opera web browser. The interface is identical in all the environments and has a consistent look and feel, and all the virtual machines created in each platform independent version are compatible with each other. The software is also extremely light, weighing in at only a 22MB download.

We tested xVM VirtualBox 1.6 on both Windows and Linux systems. On Windows, setup is extremely easy, which involves clicking on a single .MSI file. Creating a virtual machine is wizard-based and involves creating a virtual disk file, choosing a boot medium (physical CD/DVD or .ISO file) selecting memory usage, enabling a network adapter, and choosing optional device support, such as USB and audio. The Linux setup is almost as easy, but requires downloading a version specific to your exact Linux distribution, and using the native package management format of your specific version of Linux. For our tests, we used Ubuntu Hardy Heron 8.04 as the host operating system. We downloaded the Ubuntu Hardy Heron version of VirtualBox and double-clicked on it in the GNOME interface to install it, and were prompted for the administrative password to confirm.

Overall we found VirtualBox xVM performance to be excellent, especially when loaded on a 64-bit machine with AMD or Intel virtualization acceleration enabled. However, even software-based virtualization on 32-bit systems running 32-bit virtualized OSes ran acceptably. While the software could run on as little on a system as little as 1GB of RAM running a single 512MB VM, we would recommend a minimum of 2GB on the host machine for predictable performance using 512MB or 1024MB VMs. Like VMWare, VirtualBox comes with its own set of integration tools which can be installed on the guest OSes to improve performance. VirtualBox also supports Virtual Machine formats of competitive products, such as Microsoft's Virtual Server and VMWare. Be advised that if you do port one of your older VMs over, you'll want to remove the "tools" (paravirtualized device drivers) from the guest OS install before running them in VirtualBox, or you will run into a number of compatibility problems.

While VirtualBox is primarily intended for Workstation use, it can be used in a "Server" role and GUI-less by running in a special command-line invoked mode. VirtualBox contains its own RDP server, so any client equipped with an RDP client -- that means anyone with the Windows Terminal Server client installed or the Linux "tsclient" program can access a Virtual Machine remotely. However, in order to be accessible to remote machines without doing complex port forwarding thru ipchains, VirtualBox has to run VMs in a "Bridged" network mode where each VM gets a unique IP address rather than the default "NAT" mode where the host interface is shared and the address for the VM exists behind a non-accessible network. In Windows, this is as easy as clicking on "add new host interface". On Linux, this is somewhat more complicated, as each Linux distribution handles interface bridging differently. You'll want to consult the very excellent PDF documentation that comes with the product if you want to get this feature to work properly on a Linux machine.

VMWare Server 2.0 Beta 2

VMWare Server 2.0 is a significant departure from previous versions of the Server product, in that everything in this version is entirely web-based. Once installed on a host system, absolutely everything from an administrative standpoint is performed thru a browser. For many of us who were used to the native VMWare Server Console for Windows and Linux in version 1.0 and were exposed to the first Server 2.0 beta, this was perceived as a particularly stupid move, as initial performance and usability was absolutely horrible. Some of us even called for the programmers to be thrown into a volcano and a return to the old ways of the Force, and vowed to never use the product again until they switched back to a more traditional interface. VMWare assured us at the time that they were listening to our feedback, and that performance would improve, and we would soon "get" what they were trying to do.

Enter Beta 2 of Server 2.0. As fate would have it, the product significantly improved. After reviewing a number of design flaws, the programmers decided to go with a hybrid approach, where the VM provisioning and management interface was web-based, but the actual console was native, as a browser-launched plugin module on Windows and Linux. Performance under 2.0 beta 2 is now as good or better than Server 1.0, and the decoupling of the native VMWare Server client and moving to a web interface (which appears to be programmed in Ajax) now allows for more flexibility and lighter client payload on the administrative side.

However, all this Web 2.0 goodness comes with a price -- heft. Server 2.0 beta 2 weighs in at a mammoth 450MB download, and requires a fairly serious box to run with good performance. For our tests, we used a dual-core Athlon 64 X2 5000 ASUS mainboard-based PC clone with 2GB RAM, and an IBM xSeries 1U server with twin dual Xeon 3.6gGhz processors with 4GB of RAM, using the 64-bit version of CentOS 5 (a free identical clone of RHEL 5) as the host operating system. VMWare Server 2.0 also comes in a Windows version, but this version was not tested due to time constraints, and the web UI is identical regardless of what client is used. Performance on the 4GB system was excellent, and quite fast when we doubled the host memory to 8GB, but we started to see some scalability and response issues on the 2GB machine with 1024MB VMs. Additionally, we found that the only reliable browsers to use as the administrative client were the beta and release candidate versions of Firefox 3 -- Firefox 2 and Internet Explorer 7 seemed a bit glitchy with all the Ajax components of the new Web UI.

Setup on VMWare Server 2.0 on the host operating system, as with all previous versions, requires that you either use a Linux OS that has supported pre-built kernel modules built into VMWare Server 2.0's installer program, or you have the kernel sources and other key dependencies installed so that the various VMWare Server modules can be compiled. On an unpatched CentOS 5 or RHEL base OS, the kernel modules are already supported out of the box. However, should you upgrade your kernel via the "yum" on CentOS or via Red Hat Network this requires that the "gcc", "make" and "kernel-source" packages are installed prior to running the VMWare installation. The same goes for SUSE OSes. For Ubuntu guests, the "build-essential" meta package as well as "kernel-headers" needs to be installed. It should be noted that each time the kernel on the host OS is upgraded from the supported stock kernels in the vmware-server-distrib directory, the VMWare installer script needs to be re-run with these pre-requisites installed in order to recompile the key support modules. The above is also true for all guest Linux OSes running the VMWare Tools. Windows and Solaris guest tool installs are less complicated, as there is little kernel variation on these systems and the tools installer is able to deal with them out of the box.


Both xVM VirtualBox 1.6 and VMWare Server 2.0 are excellent free SMB/Personal virtualization solutions, each with its own set of advantages and disadvantages. VirtualBox has the widest range of host system support and has the lightest hardware demands, and excels for single PC personal virtualization needs, but requires more UNIX/Linux command-line skills when used as server virtualization solution. VMWare 2.0 has an excellent web-management UI with the lightest client payload, but this comes at the expense of heftier hardware requirements for good performance and a fatter software drop on the server.

Our verdict? We like both, and feel each will carve out its own specific niche. Ultimately, we'd like to see xVM VirtualBox with more user-friendly remote management capabilities, and we'd like to see VMWare Server 2.0 go on something of a diet and become more compatible with the wider base of installed browsers. Additionally, I'd like to finally see some fruit from the labor being put into the openvmtools project and get the VMWare tools built into the upstream kernel so this constant recompiling business with the kernel upgrades gets put to rest. But if this is what you have to put up with as an early adopter when you use a free host-based virtualization solution, I'm perfectly happy with either of the two.

What's your take on the two host-based virtualization contenders? Talk Back and let me know.

Topics: Linux, CXO, Virtualization, Storage, Software, Servers, Oracle, Operating Systems, Open Source, Hardware, VMware


Jason Perlow, Sr. Technology Editor at ZDNet, is a technologist with over two decades of experience integrating large heterogeneous multi-vendor computing environments in Fortune 500 companies. Jason is currently a Partner Technology Strategist with Microsoft Corp. His expressed views do not necessarily represent those of his employer.

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  • VMware has even more managability

    You have the additional capability of managing VMware Server (2.0 beta) with their enterprise-class tools in the Virtual Infrastructure suite. (That means no web front-end!) You can also automate actions without purchasing VI using their VMware Toolkit for Windows which uses the PowerShell scripting language.

    You can find out more info along these lines on their VI Powershell blog:
  • RE: Virtualization smackdown: Sun xVM VirtualBox 1.6 vs. VMWare Server 2.0 Beta 2

    I've used both VMware Server and VirtualBox. I am using for now VMware Server 1 because the first beta of VMware Server 2 was a 'sloth'. VMware Server 1 does not support USB 2.0, my only complaint.

    I'll be upgrading from 32bit to 64 in June taking openSUSE 10.3 to an AMD64 compile of openSUSE 11.0. At that point, I'll install VMware 2.0 beta 2.

    VirtualBox is definitely a contender. Correct me if I am wrong Jason, but it doesn't support 64bit guest Windows operating systems.
    D T Schmitz
  • You didn't mention the VI client for VMware!!

    You totally missed the power of the infrastruture client that can manage VMware Server 2.0. This is the same client that is used to manage the large enterprise VMware ESX based servers and adds a lot of power in an extremely easy package.

    BTW, this client was able to manage VMware server even in beta 1 when you were going to "throw the programmers in the volcano". Had you done your homework, you wouldn't have even cared about the web interface after seeing the power you have with the client.
  • RE: Virtualization smackdown: Sun xVM VirtualBox 1.6 vs. VMWare Server 2.0 Beta 2

    I ran vmware workstation with a windows guest in a linux host for years, but recently I upgraded my kernel to 2.6.23 and my virtual windows stopped working: hard crash whenever I tried to use the bridged or NAT networking. My support from vmware had expired, and posts to their forums didn't solve my problem. I switched to virtual box and have been happy ever since.
  • RE: Virtualization smackdown: Sun xVM VirtualBox 1.6 vs. VMWare Server 2.0 Beta 2

    I used to use vmware player and then vmware server but like you said its pretty heavy, especially on a machine that is about half the specs of what you tested. Then I tried virtualbox and set up and configuration was very easy. It was also a lot lighter on system resources too. So I've been using virtualbox now for creating and running vm's. Note: these vm's are just for my personal use on a my home PC, so I don't have the requirements that others would have of running servers from them.
    Loverock Davidson
  • Missed their hardware virtualization options

    Both systems can be run with hardware virtualization enabled and at least for me, it sucked bigtime on Virtualbox. Did not get to test it on VMWare but this is why I read these kinds of articles. Sad you forgot this one.
    • If we are to believe Virtualbox

      Their docs say that they're software virtualization is actually most of the time faster than using hardware virtualization anyway.
  • RE: Virtualization smackdown: Sun xVM VirtualBox 1.6 vs. VMWare Server 2.0 Beta 2

    VirtualBox works flawlessly on Vista, while VMWare can't be administered (and is thus useless) on that OS. It doesn't deal properly with User Access Control.
  • Why do you always do this!?

    Whenever there's a "which is best" article on here, it always, always ends in a tie. Just get some balls and say it how it is!
    • I have to agree....

      A tie is an impossibility with two different products aimed at to different markets.
    • Somewhat agree...

      I was looking for a little more of a head to head comparison. I switched from VMWare at home to Vbox because of ease but I wondered about performance. I VM Windows on my Ubuntu laptop with 1G of ram and its usable. I didn't want to set up VMware on this laptop to compare.
    • Are you sight impaired and brain dead

      I hate to be rude but that seems to not be a problem for a smooth talking person like yourself.
      I am legally blind and found the answer, what's you excuse?

      Try actually reading the whole article before you dive in with both feet to undermine a person's good work. After all, you want to be objective don't you?
      I do believe at the end of the article the author said he liked the Sun product more. Besides if applications are similar than the answers would be just that, similar. If you don't like the writer than don't read the writers articles. That can't be hard for someone so interested in someone else's testicles and how well they use them.
      It seems whenever I read an article like this there is always someone who thinks they would be better at writing. Of course the writer is employed in the field, are you? Can you make objective decisions and compare software at the level the author would have to to write the article?
      I'm just curious because as I can see you have extensively researched this article. Do you read so many of these that you are now an expert?
      Whatever. It is always interesting if not underwhelming to read such brilliant commentary by a highly unqualified person. Thanks because I feel so much better for having been so effectively informed.
  • Strange comparison?

    I would have thought you would compare the VMworkstation to VBox. They are more similar in target audience. Is it fair to compare Vbox on a PC to VWware on big iron. 2GB host to 8GB host seems a little slanted.

    Since Sun has released 1.6 Vbox, it now supports most USB without having to be a Unix guru and developer. I am seriously impressed with Vbox performance and expect Sun to be a big boost to the VM market. Thanks to Sun, which by the way we have a lot to be thankful for, for giving VBox a big boost.

    Just so you know, I don't work for Sun.
    • VMWorkstation isn't free

      Having a free version seems to have been the first criterion.
      • Yeah, why isn't?

        But it still is a closer product comparison...
      • Neither is VirtualBox

        At least not in a commercial environment. The full version is free for personal and evaluation use. The open source version does not include some pretty useful features, such as the RDP server and USB support.
        • persional use is wide

          if you look ath the FAQs it explains that persional use include using it at work so long as your not installing it on hundreds of PCs, it more of a reasonable use thing. so in at least small buisnesses it is free even in a comercial enviroment.
  • xVM blows away VMWare

    Hands down, no contest. Runs on any platform. Runs most major VM types. Performance as close to native as you can get right now. VBox knows that a host server shouldn't be bogged down with fiery text GUI stuff; so you can run headless and connect via VRDP to your VMs (any OS, not just Windows) and even get soun and remote USB to boot. Maybe VMWare will get there by version 4? :P Hey, we gotta thank VMWare for getting the ball rolling in the x86 virtualization arena, but today VBox is the clear innovator. When Sun finishes integration with Xen, LDoms, Zones and Containers, there virtualization portfolio will be "virtually" unbeatable.
    • Great Comment

      I agree there is something disrusptive around this potential combination. When do you think that this integration will occur with Xen?
  • RE: True Showdown Template

    Instead of bragging about this or that and being all subjective (which we are all prone to do), or just talking about general experiences, can we come up with a true showdown template?

    I see that platform independence / interoperability seems to be a point of comparison.
    I see that performance seems to be a comparison point.
    I think that we need some input on various features / user experience points to be measured.

    My experience with Virtual Box after using just VMWare Server was "WOW... that was easy!", but then later found it difficult to do what was easily done in VMWare server (have a VM that booted up every time the machine started). This was my experience, but everyones experience is different, that is the point of having a comparison matrix.

    I think we can all pitch in some ideas of things that are important to us, and come up with a pretty good matrix by which we could test VMWare Server, VirtualBox, VirtualPC and XEN. Only tested in their free forms.