Apple opens licence for server virtualization

Apple is to allow its new Leopard server OS to run in a virtual machine, the first time the company has ever changed its decades-old policy of 'one machine, one OS'.

Under the EULA for the latest version of the Mac OS X Server, section 2A includes the following paragraph: "This License allows you to install and use one copy of the Mac OS X Server software (the "Mac OS X Server Software") on a single Apple-labeled [sic] computer. You may also install and use other copies of Mac OS X Server Software on the same Apple-labeled [sic] computer, provided that you acquire an individual and valid license from Apple for each of these other copies of Mac OS X Server Software."

This permission to run more than one instance of the OS on a single machine is a change from all previous versions, which explicitly allow only one instance to run. The rest of the EULA is much as before, and includes the usual stipulation that the software must run only on Apple's own hardware. The new EULA also applies only to Leopard Server: the client version is still limited to one copy per machine.

Response from virtualization technology vendors such as Parallels, currently leading the desktop virtualization market on the Mac and which has a server version of its software due out in 2008, was positive.

Parallels marketing manager Ben Rudolph said in his blog: "This is only for Leopard Server. The ability to run OS X in a virtual machine does not apply to Leopard client (ie, the version you and I run on our everyday Macs). Each virtual machine requires a separate licence of Leopard Server, so no double-dipping with your original copy. You can only run Leopard Server in a virtual machine on Apple labelled hardware, so all of you who just had a 'Sweet! Now I can run OS X on my Dell/HP/Lenovo/other PC!' moment are still out of luck."

Mac users were sanguine. One commented: "Seems a shame you can't have Parallels running Leopard client and Tiger client (for compatibility with older software)."

One analyst pointed out that you need heavy resources to virtualize servers, which demands high IO throughput and considerable amounts of memory and CPU. Analyst John Welch told a Mac news service that Apple doesn't sell a box that's capable of being an effective server for virtual machines.

Apple has yet to comment.