Citrix Rides A Wave Of Virtualization Success

Pieces Of The Puzzle
XenDesktop: The Test Center reviewed the XenDesktop. It's bundled with XenServer, Provisioning Server and Xen Desktop Delivery Controller. The setup consists of deploying two physical servers. Server No. 1 runs the Infrastructure: XenServer with three virtual machines—a domain controller, the Xen Desktop Delivery Controller and the Provisioning server. Server No. 2 also runs XenServer and stores the OS virtual machines to be streamed.

Provisioning Server provides the streaming of the OS to clients. Performance is enhanced with the ICA protocol—a thin, remote viewing protocol that allows for SpeedScreen Progressive Display, which makes fast screen rendering.

The total cost of ownership potential with XenDesktop could be huge; "greater user density per hardware platform" is how one Citrix executive phrased it. It could be a compelling discussion between a VAR and a customer.

Deployment of XenDesktop is quite straightforward. Requirements include a minimum of 8 GB of memory and a virtualization-capable processor like AMD-V or Intel VT.

It's not yet plug-and-play on all hardware, though. Test Center reviewers attempted to install XenDesktop beta on a Dell PowerEdge T105 with a dual-core Opteron and 8 GB of memory. During installation of the XenServer portion, the install process stalled out, unable to continue reading off the optical drive.

Citrix reviewers confirmed they were aware of this issue regarding this specific Dell server and the beta release of XenDesktop, and that it will be addressed with the upcoming RC release of XenDesktop, they said.

XenDesktop integrates with Active Directory. From AD, an administrator can control what applications a user can run on a VM, and can define user permissions.

The fact that a user is connected virtually is undetectable by the user. The virtualized OS has a "disconnect" button that will keep the desktop environment in the same state when the user reconnects. If a user has a spreadsheet open, for example, that file will remain open upon reconnection when the disconnect button is used. This version of XenDesktop also supports thumb drives, which appear as network drives. For printing, the VM uses the printer driver of a locally defined system; if that driver is not available, then the system will use a universal printer driver.

Simon Crosby, Citrix's chief technology officer, offered the benefits of desktop virtualization; among them are having centralized hard disks in a data center, better desktop security, easier management of compliance policies and easier maintenance of backups. With desktop virtualization, "the desktop device becomes thinner; applications are streamed from the datacenter," he added. An additional advantage he explained is that with virtualization of the desktop, multiple operating systems do not have to be maintained.

XenApp: Formerly Presentation Server, Citrix will release a revised version of XenApp this summer. The company did not have a beta release ready for a hands-on review. However, they did share some of the new features. One of the major enhancements is the capability of new XenApp to work with Microsoft's Windows Server 2008. The software went through a refactoring process to take advantage of the security and reliability of 2008. An additional new feature—streamed applications—can be accessed when a user is offline, a benefit for mobile users. There are two components to this technology: an isolated environment on the client, and an application stored inside that environment. The application can be executed whenever a user wants, and wherever that user is located. Applications do not have to be installed. Any updates to the application can be done remotely, without user intervention.

This will take application virtualization to new heights and potentially wipe out significant overhead from an enterprise. Countless hours of configuration, PC by PC, notebook by notebook, would simply go away.

Citrix and Hewlett-Packard Integrated Products: Citrix also has worked with HP to provide a thin client that can handle workhorse machines like CAD stations. HP's Blade PCs will support XenDesktop as of May this year.

The Test Center also took a look at HP's Select Server—a jointly developed server by Citrix and HP, with XenServer 4.1 integrated. This is a beefy server—with 4-way, dual-core AMD Opteron 2.6-Ghz processors and 8 GB of memory.

The server comes with a graphical interface, which allows for a very easy setup of XenServer. Once configured, virtual machines are set up via the HP Proliant Virtual Console. The interface also includes a system console for Linux commands. But there may be some quirks like one we found in a beta unit we examined in the Test Center lab. For example, when defining an installation source to create new virtual machines, the virtual console wouldn't recognize a USB CD-ROM mounted in Linux. While this may be just a quirk in the beta unit, it did eat up several hours of testing time in the Test Center lab and could easily stall a solution provider trying to roll it out for a customer. If that becomes a nonissue in general release, though, it could incredibly speed up the time to create and deploy a virtual environment.

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