Practical Technology

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Microsoft’s Linux driver offering planned for years


‘m really not sure why everyone is so surprised that Microsoft submitted the driver source code for four Microsoft Hyper-V drivers for inclusion in the Linux kernel under the GPLv2 license. You see, Microsoft and Novell have been working on this for over two years now.

These drivers, jointly called the Linux Device Driver for Virtualization, when added to Linux, gives any distribution using them the ability to run on Windows Server 2008 and its Hyper-V hypervisor technology. Server-level virtualization doesn’t get people excited the way the desktop models, like Sun, now Oracle’s, VirtualBox, but it’s actually much more important for businesses. By enabling companies to run more than one server, or a mix of server operating systems, on one hardware platform you save both energy and hardware costs. So, for Novell and Microsoft, which with their partner Citrix is out to knock out VMware and Red Hat, making Hyper-V serve as a bridge between Linux and Windows Server 2008 is a major part of their fight plan.

So, back in February 2007, Microsoft and Novell announced that they were working on making Windows and Linux’s virtual machines-Hyper-V and Xen respectively-work and play well with each other. To quote Sam Ramji, then Microsoft’s director of platform technology strategy, the two companies had created a “Joint Interoperability Lab, which “will be around for the long term, and will focus on interoperable virtualization between the Windows and SLES (SUSE Linux Enterprise Server).”

Microsoft and Novell had actually already been working on this for time. Indeed, Intel was also working with Novell on these plans. That same month, Intel and Novell told the world that they were releasing of paravirtualized network and block device drivers. These drivers enable Windows Server to run unmodified in Xen virtual environments on Linux.

Novell and Microsoft also further explained that together the companies would work on jointly developing a virtualization offering that would let Windows Server administrators run SLES as a virtualized guest on Microsoft Virtual Server 2005 R2. They also announced that they were working on getting SLES to run as an ‘enlightened guest’ on Server 2008. All of this has since come to pass.

In short, there was really nothing at all surprising about this announcement. It’s been in the works for over two years.

With that in mind, I find it a little disingenuous for Greg Kroah-Hartman, the Linux driver project lead and a Novell fellow, to tell John Fontana of Network World that “Another kernel community member noticed the [Microsoft] drivers and pointed them out to me Through the contacts I have at Novell and through the Microsoft/Novell interoperability agreement, I contacted Microsoft and worked out the details.” That may well have been how it worked out that this code made it into Linux, but it must always have been part of Microsoft and Novell’s overall plan for peaceful Linux and Windows co-existence.

With all that in mind, I don’t see any of this as really being surprising. Microsoft and Linux fans love to throw verbal brickbats at each other, but network administrators and server companies love interoperability. Microsoft isn’t giving anything away. These drivers just make it possible for Linux servers to run as virtual machines to run on Windows Server 2008. Thus, anyone who ever uses this code is going to have to buy a copy of Windows Server first.

I don’t see this as a sign that Microsoft is learning to appreciate the value of open source. I see this as a purely pragmatic view to boost the sales of their own products and nothing more or less.

A version of this story was first published in ComputerWorld.

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