For all those who haven't yet committed to VMWare for their virtualisation needs, Citrix have released the enterprise version of their Xenserver hypervisor for free.

While Citrix haven't been selling Xenserver for long, the product (based on the Xen open source hypervisor they purchased last year) has an excellent reputation in real world implementations.  The most impressive is Amazon's E2 cloud, utilising Xen to virtualise thousands if not millions of servers.

The newly free product includes a 64 bit hypervisor and some impressive management tools, providing much of the ESX class functionality such as live migration and virtual pool management.

The move is designed to counter Microsoft's Hyper-V product that comes free with Windows Server 2008.  The problem with going down the Microsoft path is that it's only the basic hypervisor that comes with Server 2008.  For any advanced management features you have to purchase System Center: Virtual Machine Manager (VMM) or go down the VMWare ESX path.  Citrix are hoping that mid-size firms will start using the free version of Xenserver rather than the more limited vanilla Hyper-V or expensive VMware ESX.  Once they're hooked on Xen for virtualisation, Citrix are hoping that firms will purchase their "Essentials" management tools that provide more advanced features such as automated lab management and virtual storage clusters.

A version of Essentials is also available to manage pure Hyper-V installations, as an alternative to System Center: VMM.

More here: http://www.crn.com/software/214502446