The market for server virtualization software appears to have gotten a whole lot more crowded this week. Not only did Oracle announce free server virtualization software at the Oracle Open World conference, but Microsoft and VMWare also made announcements of competing free offerings. And this morning at Oracle OpenWorld Sun announced their plans for virtualization also, known as xVM with support from Intel, AMD, The market for server virtualization software appears to have gotten a whole lot more crowded this week. Not only did Oracle announce free server virtualization software at the Oracle Open World conference, but Microsoft and VMWare also made announcements of competing free offerings. And this morning at Oracle OpenWorld Sun announced their plans for virtualization also, known as xVM with support from Intel, AMD, Symantec and MySQL among others. Rich Green, head of Software at Sun, demonstrated Sun’s xVM virtualization server and the xVM Ops Center management software console with a live demo deploying a workload to some Sun servers in Denver. (Luckily, they had good connectivity, which is always a risk at a conference!)They’ve also announced OpenxVM.org, a resource providing open source tools to support their effort. I’m on my way to the press conference to see what additional Q&A there is for Jonathan Schwartz on their announcements. I suspect a lot of the questions will be about Sun’s announced partnership with Dell, who will now distribute Solaris. More on that later. Anyways, back to virtualization… So add to all these VM newcomers the fact that virtualization is also available from Red Hat, Novell SUSE and from Citrix (who acquired XenSource), it’s enough to make your head spin. Why so many competing offerings? Actually, there aren’t that many. Most of the virtualization software out there (except VMWare and Microsoft) are using the same Xen virtual machine monitor or hypervisor. And in fact, Xen is available in just about every major version of Linux. So whether you’re using Citrix, Sun, Red Hat or Oracle’s virtualization layer, it’s basically the same core technology. That’s good, since it means that the technology will likely mature faster. (Or at least, that’s my bet!)Microsoft’s technology is a little earlier in its lifecycle and will come some time after the introduction of Windows Server 2008, the long delayed “Longhorn” release. Microsoft said they would make available their Hyper-V virtualization technology in August 2008 and that it will run “bare metal” and would not require users to run Windows Server 2008. So in theory that means Microsoft would support other platforms, including Linux. But we’ll have to wait and see if Microsoft is serious about this. As it stands, most people put Microsoft at least a year behind the competition in virtualization. Despite some occasional PR from Bill Hilf, Microsoft hasn’t really shown a whole lot of support for open source, but that could change if they start getting the mandate from their customers. And why wouldn’t they? Open Source