by Brian Boyko
Editor, Network Performance Daily

Apple hasn't made many overtures to business; the announcement that King Jobs had deigned to allow enterprise apps in his iPhone fiefdom took many by surprise. Apple's previous attempts at wooing enterprise customers, specifically the Xserve, seemed, in my opinion, more like a half-hearted reassurance to shareholders that they weren't completely ignoring the enterprise market.

Here's a telling point about Apple's attitude: Even though virtualization is one of the most important trends in enterprise computing, Apple makes the only operating system which cannot be run as a virtualized OS on generic hardware. It didn't allow Leopard Server to be run as a virtualized OS even on its own hardware until October 31st of last year.

While it's also true that Microsoft had - past tense - clauses in Vista EULAs which made it illegal to run Vista Home Basic and Vista Home Premium (but not Business, Enterprise, or Ultimate), as a virtual machine, those restrictions were eventually lifted in late January of 2008 - most importantly there was no deliberately imposed technical stumbling block that prevented those OS versions from being virtualized.

(One commentator, who I cannot remember, suggested that Microsoft's awkward anti-virtualization positioning was a move to prevent Apple from offering Parallels Desktop and a virtualized Vista pre-installed on new Apple consumer computers - but the ban has been lifted and Apple hasn't made any deal like that.)

Apple's MacOSX, on the other hand, checks to make sure it's running on Apple hardware, and will not run, otherwise. There are hacks to get around this, I'm sure, but they're much more difficult to pull off, may have stability problems - oh, and there's that whole "it's quite illegal" thing, too.

You can run MacOSX as a virtual server on an Xserve. But then it gets back to the application developers.

Enterprise application developers know today that they can pretty much choose their choice of platform. Have a Linux app but want to sell it to a Windows shop? Virtualization comes to the rescue. Windows applications on a Unix flavor? Again, same deal (though developers might have to pay for a copy of Windows to bundle with virtualized apps if the company doesn't already have a Windows virtual machine running.) But this incentive does not exist for the Macintosh platform. Who would develop a networked server application for the Macintosh platform knowing that you can only sell it to a company that made a big investment in Xserves? Especially since you can just code it for Linux or Windows and let Apple-only shops run it in virtualization.

Additionally, Microsoft has developed an optimized Windows Server 2003 version for virtualization - the Datacenter edition, and various Linux developers have scaled-down versions of the Linux OS for virtualization, including Ubuntu JeOS. We were not able to find a stripped-down version of Apple's Leopard Server. At any rate, running a "full" operating system in virtualization increases overhead and can impact server response times and, therefore, application performance.

Since there's this disincentive for enterprise application developers to develop for the platform, and a comparative performance hit on the platform that should cause network engineers to think twice about the platform, what, exactly is the utility of a MacOSX server?