Mac OS X Lion expected to further ease Apple's virtualization restrictions

Can run up to two additional copies of Mac OS X in a virtual machine

Thanks to virtualization, running Microsoft Windows applications on Apple hardware has become a popular way for consumers to dump their PCs in favor of using a Mac. Much to the chagrin of Microsoft hardware partners, this is yet another reason for Apple's growing hardware success.

In contrast, Apple has only grudgingly allowed its own Mac OS X to run on a virtual machine, and even then they've been extremely restrictive with that policy.

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If you remember the long, drawn-out discussions in the past, the policy on virtualizing Mac OS X was clear. Apple stated that the license allowed you to install and use only one copy of the Mac OS X software on a single Apple-labeled computer at a time. It was a one-license, one-machine type of end-user license agreement (EULA), which pretty much ruled the Mac OS X out as a guest operating system, though both VMware and Parallels said it was "possible" to virtualize the OS.

Fast-forward to the end of 2007, when Apple eased its licensing restrictions a bit and began permitting limited virtualization of Mac OS X with the release of Mac OS X Snow Leopard Server. That permission came with three major caveats: First, you could only run Mac OS X virtual machines on a single Apple-labeled computer. Second, you needed to acquire an individual and valid license from Apple for each of these other copies of Mac OS X running in a VM. Third, this applied to only the more expensive Snow Leopard Server version of the OS, leaving the more widely used client version out in the cold.

But there is good news for Apple enthusiasts. The latest version of the OS X operating system could be hitting virtual shelves within days -- according to various news reports, Apple has already released the gold master of OS X Lion to developers, which suggests that the official release of OS X 10.7 is but a few days away. As of yet, Apple hasn't given an official release date for the OS update other than saying it is expected to arrive sometime in July.

Other good news is a possible licensing change that could once again ease the virtualization restrictions placed around Mac OS X. The latest reports show that OS X 10.7 is blurring the lines between OS X Server and OS X Client, and this new release comes with a less restricted EULA:

(iii) to install, use and run up to two (2) additional copies or instances of the Apple Software within virtual operating system environments on each Mac Computer you own or control that is already running the Apple Software

According to this line, users should be able to run up to two additional instances of OS X Lion on the same machine without the need to purchase extra licenses from Apple. Presumably, this would take place with existing virtualization hypervisors like VMware Fusion, Parallels for Mac, and Oracle VirtualBox.

Being able to run multiple copies of Lion on the same machine will help users verify that a software update from Apple doesn't cause compatibility issues with existing software applications. It will also help with having a known-good environment for testing purposes or for trying out new applications in a controlled manner.

But it remains a mystery whether users will be allowed to virtualize a copy of the Snow Leopard client, so they can still run older applications that may not be compatible after upgrading to Lion.

Hopefully, virtualization pressure from consumers will push operating system and software manufacturers to keep adjusting and changing their licensing policies to make them more virtualization-friendly. This looks like another great step coming out of Apple, but there is still a lot of room to grow.

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