Citrix Tools Show Virtualization Isn't All About The Hypervisor

Tag : Machine Tool Body
That neutralizes the hypervisor as a vendor lock-in and gives datacenter managers new flexibility in building virtual appliances anddeciding where to deploy them. OVF will force suppliers to stopcompeting on whose virtual machine gets generated, and insteadshift the race toward who's building the most flexible, manageablevirtualized environment.

For example, a virtual machine using Microsoft's Hyper-Vhypervisor, and consisting of Windows and a Windows applicationassembled to the OVF spec, can run under Citrix XenServer orVMware's ESX Server--and vice versa. That's why, although Citrixmade the first big move, "all the vendors are interested in OVFcapabilities," says Forrester Research analyst Frank Gillett.


The Citrix tools will convert virtualized files into Microsoft'sVirtual Hard Disk format, which is used for formatting a virtualmachine as a set of files stored to disk. The tools captureapplication and virtual machine configuration data in an XML schemaset by the Distributed Management Task Force, the standards bodythat ratified OVF, says Simon Crosby, Citrix's virtualization CTOand XenSource's founder.
VMware actually proposed OVF as a standard. VMware saw rivalsMicrosoft and Citrix align around Microsoft's VHD. While VMware'sVMHD is the industry's dominant format, the company risked beingtypecast as a lock-in risk, or even a backwater, if VHD became morewidespread. So VMware proposed OVF in February 2007 as a standardand embraced building virtual appliances so that each workload hadits own VM, operating system, and applications. XenSource--the opensource company built around the open source Xen hypervisor--agreedto co-author the draft standard, and other vendors, including Dell,Hewlett-Packard, IBM, and Microsoft, joined in. Citrix boughtXenSource in August 2007.