It's no secret that a virtualized server infrastructure is one of the best ways to reduce capital expenditures by virtue of the technology's consolidation capabilities. But anyone looking to increase data center performance and enhance efficiencies will find themselves up against a brick wall unless they unite their virtualization platform with an equally robust storage environment.

One by one, the major virtualization providers seem to be getting that message.

This week brings news that Citrix Systems has teamed with NetApp to integrate access to NetApp storage appliances into the XenServer platform. The connection will be made via a specialized adapter for the NetApp Data ONTAP system that allows managers to provision and configure storage from the XenServer 4.1 management system. Among the tools available through XenServer will be instant thin provisioning of virtual disk images (VDIs), as well as VDI cloning, snapshotting and deduplication -- all without the need for additional scripting, downloads or licensing.

The deal comes at a time when storage vendors are starting to express increasing unease with the new Storage VMotion system by market leader VMware. The system is intended as an integrated storage management system that users could deploy without having to reconfigure their virtual machine infrastructures. But according to this blog by The Burton Group's Chris Wolf, third-party storage vendors feel it diminishes the value of their add-ons to the ESX server and are increasingly looking to Citrix, Microsoft and Virtual Iron for partnering deals.

It was only last month, in fact, that NetApp came out with a new set of storage and data management solutions for Hyper-V, along with Windows and SQL Server 2008. The tie-up allows Microsoft users to provision both servers and storage in a coordinated manner, improving storage efficiency and availability.

Virtual Iron, meanwhile, kicked off the new year with an agreement with Falconstor to integrate their respective server and storage solutions with an eye toward improving data migration among and between various storage systems and virtual machines.

Of course, being majority owned by EMC ensures that VMware will likely have a strong storage component no matter what happens. And indeed, third-party software firms still seem eager to get on VMware's good side, as evidenced by 3PAR's recent announcement that its InServ storage server has received ESX 3.5 certification.

Integrating server/storage systems is key to devising robust virtual environments, but they make up only two legs of a three-legged stool. The final leg is networking, which will likely require some bandwidth attention once all those new virtual machines start requesting data from newly provisioned storage.