Cats & dogs, aka Linux and Microsoft, will work together on Azure.

Ace Microsoft reporter Mary Jo Foley swears she's not drinking. Microsoft really is getting ready to enable customers to make Linux and Windows virtual machines (VMs) persistent on Windows Azure, its public platform-as-a-service (PaaS) cloud service.

That Microsoft was going to enable users to set up persistent VMs on Azure came as no surprise. While Azure has persistent storage, its inability to keep a VM persistent has annoyed many people, and not just Linux server managers. I know several SharePoint and SQL Server administrators who've avoided Azure because of this lack. There are ways to hack your way around the lack of a persistent Azure VM, but they're not easy.

According to Foley's sources, Microsoft will launch a Community Technology Preview (CTP) test-build of the persistent VM capability in the spring of 2012. Microsoft itself has been close-mouthed about support for persistent VMs and supporting Linux on it in particular.

So why is Microsoft, ever so quietly and reluctantly doing this? Because its customers are demanding Linux support. Oh the irony!

For several years, starting with SUSE Linux, Microsoft has supported Linux on its Hyper-V virtual machine platform. Today, Microsoft also supports Red Hat Enterprise Linux (RHEL) and CentOS. There were also rumors last summer that Microsoft would support Debian and Ubuntu on Hyper-V, but nothing has come of that. Microsoft wasn't supporting Linux then because it loved Linux. It did this because its customers demanded Linux server support and now its customers are once more pushing Microsoft into supporting Linux, this time on the cloud.

Now, Microsoft's business customers are demanding that same VM support on the cloud and Microsoft will be giving it to them. As Foley reported, "Running Linux on Azure has been a surprisingly big business-customer request." That doesn't surprise me. The Cloud Market analysis of operating systems on the Amazon Elastic Compute Cloud (EC2) found that there were 6,556 Linux instance running compared to 1,120 Windows instances. By almost six to one, cloud users preferred Linux over Windows.

But, just because users want Linux doesn't mean that Microsoft will make it easy for them to get it. Instead, Linux users will need to provide their own Linux VM images. At this time, Azure only supports Virtual Hard Disk (VHD) images for its VMs. The new persistent VM support will be available as a Community Technology Preview (CTP) test-build in spring 2012.

If something goes wrong with Linux on Azure, I'm sure Microsoft will put the blame and support burden on the companies running Linux. That will be a mistake.

Microsoft's business customers are speaking, and they want Linux. If Microsoft doesn't deliver the goods, Amazon, Red Hat, and VMware, to name three of its cloud rivals, are already happy to fully support Linux users on the cloud.

Cat and dog image by hoangnam_nguyen, CC 2.0.

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