Is VMware's ESX server derived from Linux?

Is VMware's ESX server derived from Linux?

Summary: Linux guru Mike MacCana is claiming that VMware's ESX server application is derived from Linux, and because of this cannot legally be redistributed as proprietary software.


There nothing like a huge IPO and being described as the hottest tech stock since Google to attract attention to your company, and it seems that this is what's happened to VMware.  Writing on VentureCake blog, Linux guru Mike MacCana is claiming that VMware's ESX server application is derived from Linux, and because of this cannot legally be redistributed as proprietary software.

The issue, as MacCana describes it, is that when a system running ESX boots up, the kernel is Linux.

Here’s how MacCana sees the problem:

Proprietary drivers for Linux kernel have an interesting licensing situation. Unlike the license for higher level libraries, which allow those libraries to be used by both Open Source and proprietary software, the license for the Linux kernel specifies that software based on the Linux kernel must be licensed under the same license.

So the core of MacCana’s argument is that if the kernel relies on Linux, it has to be open source, yet ESX is not.  If the kernel didn’t require Linux to load it could be considered to be derivative and therefore could be legally distributed.

The problem goes back a fair while.  Back in August 2006 there was a post on the Linux kernel mailing list made by the Linux SCSI storage maintainer, Christopher Helwig in which he responds to a post from VMware's Zachary Amsden:

Until you stop violating our copyrights with the VMWare ESX support nothing is going to be supported. So could you please stop abusing the Linux code illegally in your projects so I don't have to sue you, or at least piss off and don't expect us to support you in violating our copyrights. I know this isn't your fault, but please get the VMware/EMC legal department to fix it up first.

There was no reply from Amsden.

VMware has drawn attention to itself.  it’ll be interesting to see where this goes.

Topics: VMware, Linux, Open Source, Servers

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  • If you use it...

    honor the license.

    The video on the linked site leaves no doubt that ESX is using Linux.

    There are some hefty cost benefits of reusing code. In exchange for this usage the license must be respected. VMware can choose to abide by the GPL or they can create their own proprietary OS.
    Tim Patterson
  • WTF?

    Vmware claims that with Vmware 3.x, they replaced the part the touches the bare metal with their own code, and the "Linux" in vmware run atop vmware in a virtual machine.

    Are these people saying vmware is lying?
  • Adrian...

    I find this statement funny from the link you provided well the whole purpose of VMWare is to allow more than one OS(Kernel) to share the hardware.

    "So according to VMware, ESX actually has two kernels that run directly on hardware - the vmkernel, and a Linux kernel. This sounds a bit odd, given a computer can only run one kernel at a given time ? otherwise which one determines who gets access to the CPU, memory, and other hardware?"
    • It is not running 2 kernels on hardware

      My understanding is that ESX uses the Linux OS as a "bootstrap" during bootup. Once the Linux kernel booted, it starts up the ESX OS which then "virtualizes" the Linux kernel and inserts itself between the hardware and the Linux OS. Don't ask me the details, this was how it was explained to me. So, from that point on, the Linux kernel is running virtual on ESX.

      The Linux kernel is called the "COS", short for Console OS. Once it has been virtualized by ESX, its purpose is merely as a management console that you use to manage ESX functionality with. That is why it [b]looks[/b] like ESX itself is Linux, because you are managing ESX via the virtualized Linux OS running on top of it. My understanding is also that the COS is being phased out as the ESX OS gets it own management features added.

      So, just because Linux takes part in the bootup and management process, does not mean that the ESX OS itself is Linux.

      Anybody that claims that ESX is based on Linux need to provide some proof or back down from creating false rumors. It is pretty sad that people feel they need to damage VMware's reputation during this important phase of their IPO merely because they have a hunch about something but have no real proof.

      Of course the other thing this does is make it clear to any company that using Linux in any way, shape or form could come back to bite them. So which is better then: Going with Linux and all of the unknown legal ramifications, akin to stepping into a minefield, or licensing a proprietary OS and at least having a clear understanding of what the legal ramifications are?

      I think people will start thinking twice about using Linux so I don't see how spreading these unconfirmed rumors helps Linux in any way, it only harms it.
      • The question is...

        Is ESX dependant on using the console or any other part of the Linux kernel to operate. If it is and that code is redistributed as part of a proprietary package then it violates the GPL v2. It's really that simple.

        No one is saying don't use it what's being said is use it under the terms of the license. There's no rocket science here.


  • Hmmm, interesting

    If VMWare is using Linux illegally this will not be good for them. It could also, if it goes to court set a precedent that if successful in court, would allow Linux developers and vendors alike to challenge many other closed source vendors proving they do not have GPL code in their systems. ]:)

    Could be fun times!
    Linux User 147560
  • Catch 22

    This just demonstrates that using any portion of GPL licensed code could produce full disclosure of all source code that is dependent on that single piece of GPL licensed code...seems like the GPL is being used as a lever to "encourage" disclosure of everything else even remotely associated with it.

    If they VMWare is in fact using the Linux Kernel then should they get away with it, or do they work out some kind of arrangement?

    Whatever the outcome everyone loses.