Microsoft has created its own cut of FreeBSD 10.3 in order to make the OS available and supported in Azure.

Jason Anderson, principal PM manager at Microsoft's Open Source Technology Center says Redmond “took on the work of building, testing, releasing and maintaining the image” so it could “ensure our customers have an enterprise SLA for their FreeBSD VMs running in Azure”.

Microsoft did so “to remove that burden” from the FreeBSD Foundation, which relies on community contributions.

Redmond is not keeping its work on FreeBSD to itself: Anderson says “the majority of the investments we make at the kernel level to enable network and storage performance were up-streamed into the FreeBSD 10.3 release, so anyone who downloads a FreeBSD 10.3 image from the FreeBSD Foundation will get those investments from Microsoft built in to the OS.”

Code will flow both ways: Anderson says “... our intent is to stay current and make available the latest releases shortly after they are released by the FreeBSD Release Engineering team. We are continuing to make investments to further tune performance on storage, as well as adding new Hyper-V features – stay tuned for more information on this!”

Microsoft says it will support its distribution when run in Azure.

Redmond's rationale for the release is that plenty of software vendors use FreeBSD as the OS for software appliances. That reasoning was behind Microsoft's 2012 decision to ensure FreeBSD could run as a guest OS under Hyper-V. In your own bit barns, your guest OSes are your own problem. Microsoft clearly decided it needed something more predictable for Azure, although it has in the past allowed custom FreeBSDs to run as cloudy VMs.

Of course Microsoft has also allowed Linux on Azure VMs for years, so news of the FreeBSD effort feels like an effort to ensure the platforms cloud users want are available rather than a startling embrace of open source to rank with Azure's don't-call-it-a-Linux-for-switches or the announcement of SQL Server for Linux.

But it's still just a little surprising to see Microsoft wade into development of FreeBSD: this is not your father's Microsoft.

One last thing: when Microsoft announced it would ensure FreeBSD runs on Hyper-V, NetApp was one of its collaborators. NetApp knows FreeBSD inside out, because Data ONTAP is built on it. But NetApp is absent from the vendors listed in Microsoft's announcement of its FreeBSD efforts. Which might put the kybosh on our imagined cloud-spanning software-defined NetApp rigs. ®