Citrix customers who have tested the company's first attempt at a bare-metal client hypervisor, XenClient, say it isn't yet suitable for production because of hardware incompatibilities, bugs and other limitations. But Citrix says changes will come this year.
XenClient 1.0 became available last May, and the first Service Pack became available in January. Citrix plans to issue the next major release this summer. By the end of the year, the XenClient hardware compatibility list (HCL) will be much longer, with support for graphics* chips other than Intel'ss, and it will be production-level, said Peter Blum, Citrix's XenClient product manager.
Here, Blum answers questions about XenClient and its roadmap.
One of the biggest complaints I hear about XenClient is about the limited HCL -- especially that it supports only Intel vPro chips. When will that change?
Peter Blum: The biggest roadblock right now is support for non-Intel systems, so by the end of the year, we will support Nvidia and AMD [graphics*] chips; those are the other most widely used chips. But you'll always get best security and performance with Intel vPro.
Initially, we picked the highest-volume laptops sold to the enterprise, and there are 25 machines on our HCL based on that. But a lot of the noise around the HCL is from early adopters. Many of those customers spec out their own systems and have different needs than the typical user.
Many people consider client hypervisors to be the answer to offline support for virtual desktop infrastructure (VDI). Is that its main use?
Blum: I've been surprised at the number of early adopters who want to use it run multiple copies of Windows on one machine. Others use it to separate images for security reasons or to lock down a corporate image and run a separate sandbox image.
There are also plenty of people interested in the management benefits of running VMs [virtual machines] on a client hypervisor. And when you have a client hypervisor with a UI [user interface] on the system, users can do self-service imaging, self-service recovery and other things.
Those people running Windows XP and Windows 7 on one machine, how do they go about licensing? A lot of people are confused about how Microsoft licenses client hypervisors.
Blum: Large Microsoft customers have Software Assurance, and that covers their Windows licenses to run up to four instances. If you aren't an SA customer, you can purchase a [Virtual Desktop Access] license pack from Microsoft, or you'd have to buy separate retail licenses for each instance of Windows you're running.
Another complaint is about the need to install XenClient on user machines, especially for companies with "bring your own PC" (BYOPC) programs. How should customers address this?
Blum: When we came out with XenClient, we initially positioned it as a BYOPC, but we aren't now because of the HCL. XenClient can't be run on a consumer laptop from Best Buy -- it must be retrofitted.
For BYOPC, we suggest using XenApp offline streaming and XenVault to deliver apps on top of an OS and run them in isolation; XenVault gives you encryption. Enterprises can put XenClient on the laptops they own.
Do you use XenClient on your own computer? And if so, what for?
Blum: I do, and I have since before the release. Right now, I have personal and business VMs running on a Dell laptop. It took me a couple days to separate all the personal and business stuff because it was all mashed together, but now I have office and business apps running on my business VM and photos, iTunes and other personal stuff on the other VM.
So are you able to play iTunes and videos and get the same type of performance you would if they were running on a traditional PC?
Blum: Yes, MP3, video, [Windows] Aero stuff, the 3-D experience -- it all runs with native performance because we worked with Intel to get that level of performance.
Running video and playing music must really eat away at the battery when you are running two operating systems. People testing XenClient say battery life is a problem and that batteries die 40 to 50% quicker. Is Citrix doing anything to address that?
Blum: The hypervisor itself isn't using too much power, but if you are running two copies of Windows and actively doing stuff in each one, yes, it eats away at the battery because you are running two operating systems. It really just depends on what you are doing.
A XenClient tester asked me to inquire about the nine-VM limit. Why nine?
Blum: There is a UI limit of nine, but the XenClient hypervisor is the same as the XenServer hypervisor, which is very scalable and supports 130 VMs. For the use cases we've seen, two or three VMs is what the mainstream enterprise will use. But you could run 20 or more VMs if you had enough memory and CPU on your machine.
We are also making improvements to the Citrix Synchronizer. We are putting in more management features and more capabilities that will allow people to better scale their deployments.
*Following publication of this article, Citrix clarified that XenClient will not support AMD x86 chips. The company will support Intel x86 chips along with AMD (ATI) and Nvidia graphics chips. Blum said XenClient can run on non-vPro Intel chips as long as the chip includes Intel VTx and VTd technologies.