Levin made the announcement as he asked for Microsoft be allowed to join a Linux security list.
It should not really come as a shock. Enterprise computing is mostly Linux and Windows Server has been declining for years. IDC said in 2017, Linux had 68 percent of the market.
Native Azure services also run on Linux and Microsoft is building more of these services. For example, Azure's Software Defined Network (SDN) is based on Linux.
Apparently, it is all part of Microsoft’s realisation that open source was something that every developer can benefit from.
There are eight Linux distros available on Azure. And that's not counting Microsoft's own Azure Sphere. This is a software and hardware stack designed to secure edge devices, which includes what Microsoft president Brad Smith declared "a custom Linux kernel".