I just stumbled upon a press release from VMware. The so-called Open Virtual Machine Disk format is “openly available, downloadable and free of charge to encourage use by all developers and software vendors.” It seems that up to now it’s not yet downloadable though. You have to send an e-mail to VMWare first.

I think that this is a step in the right the direction. Although it is hard to believe the reasons they cited in the press release:

We see the broad use of a common virtual machine disk format leading to more products to choose from, along with interoperability across customers’ environments.

I think, the real reason is more likely its opposite. VMware is now fighting on two fronts. Their biggest rival is Microsoft. Sooner or later, they will integrate virtualization technology in their server operating systems. Now it is unlikely to make it in the Longhorn server in 2007.

The second front is the Open Source Community. Xen is getting more and more fans, and it is only a matter of time, until it will be ready for use in enterprise environments. Check out this new eWEEK article about the topic.

So, I think, the real reason for opening its disk format is that VMware simply wants to be the company that sets the standards in the virtualisation technology. VMware can only hold its market share, if everyone recognizes them as the leader in this field.

This is also the reason why they plan to give away their VMware Server (formerly GSX Server) for free. The more people associate virtualization software with VMware, the more people will buy their enterprise product ESX Server. By the way, I am currently testing the VMware Server beta. I probably will blog about it here one of these days.