Citrix has officially released their client hypervisor, called "XenClient." While this is something that we've been anticipating for well over a year, it appears that this "v1" has some pretty big limitations, and in fact many of the cool features are marked as "experimental."
We've been talking about client hypervisors ad nauseam on BrianMadden.com (including when you don't need them and when I think they'll finally catch on), so there's no need to go into the "what" and "why" right now. Suffice to say, whether you believe in them or not, Citrix releasing XenClient 1.0 is a big deal.
XenClient won't be a standalone product per se; instead it will be bundled into and included free with XenDesktop. There's also a "XenClient Express" which is a free edition that anyone can download and play with. (You can use the free edition on as many clients as you want, but central management, image delivery, and backup is performed by a server component called the Citrix Synchronizer, which is only free for use with up to ten clients.)
XenClient is based on the 64-bit version of the open source Xen hypervisor, and Citrix is officially supporting client VMs running the 32-bit versions of Windows XP, Vista, and 7, as well as the x64 version of Windows 7.
XenClient 1.0: Full of limitations?
Downloading and installing XenClient is pretty straightforward -- just make a boot CD from the ISO, configure some BIOS settings, click "next" a few times and you're done! But after reading the fine print you'll start to notice some weird things.
First is that you should keep in mind that Intel and Citrix have a relationship around XenClient. While details of their partnership are officially secret, word on the street is that Intel paid Citrix a lot of money for Citrix to ensure that XenClient only supports Intel vPro-based machines. And if you look at the meager hardware compatibility list that XenClient will actually run on, you'll see that yes, these are all vPro devices.
What's interesting is that about a month ago I blogged about Intel vPro and basically wondered why Intel forced ISVs like Citrix and RingCube to require it and wondered whether there were any real-world advantages to vPro? The defenders of vPro cited examples like TxT (Trusted eXecution Technology) as example of how vPro is awesome with client hypervisors, but then in the XenClient 1.0 User Guide we learn that TxT and TPM are not supported by XenClient!?! WTF???
And then let's not forget that in order for a laptop to have a vPro sticker on it (and, by extension, for it to work with XenClient), it has to have the complete Intel chipset, which means Intel integrated graphics only instead of Nvidia GPUs. (Although I guess this doesn't really matter since 3D support is classified as "experimental" in this release anyway... <sigh>)
At this point I'd like to re-ask my question from last month: Why does XenClient require vPro? What benefits to customers get from this?
Speaking of "experimental..."
So yeah, 3D graphics support is experimental and not officially supported in XenClient 1.0 at this time. Unfortunately it's not the only experimental feature.
"Secure app sharing" is also experimental. This is the feature that is essentially like seamless windows from one VM to another -- meaning that a user can access apps from multiple VMs via a single desktop instead of having to switch to each full desktop to use that VM's apps. Even if this wasn't experimental, configuration looks like a beast, based on local configuration XML files. Yikes! (Check out the User Guide Page 36... ugg!)
XenClient's "Dynamic Mode" is also released as an experimental feature. Dynamic mode is the "shared master" or "one-to-many" disk mode for XenClient, where a single gold master image on the network can be used by many different users at once. In the world of XenClient, users ought to be able to receive and refresh their base images while retaining their personal settings (documents, etc.), although right now that's not supported. Instead XenClient only supports the "one-to-one" or "persistent" image mode (called "Static Mode") where each user "owns" his or her own image. (So how do you update these things? SCCM? Symantec Client Management Suite? Why exactly are we using XenClient again?)
But before you spend any time trying to get the experimental Dynamic Image Mode to work, check out this little gem from the Admin Guide (p24):
Note: The user must manually join an Active Directory domain if required after downloading a Dynamic VM image mode VM.
By the way, the Dynamic Mode is completely different from Citrix Provisioning Server (PVS), which you could use with XenClient as long as your clients were always LAN-connected to your PVS host (which means desktop only, although in that case I think you'd just use PVS with bare metal since XenClient doesn't support enough different desktop hardware SKUs to necessitate a client hypervisor in the first place)!
And then there's the "known issues" list...
And just in case you still have any remaining excitement about XenClient 1.0, there are a whopping 59 (!) "known issues" in the Release Notes. Fifty-nine! And this is a product with a VERY limited HCL which only supports four different guest OS platforms!
Here's a sample of 10 of the 59 known issues. As you read through this, keep in mind that Citrix is actually trying to sell XenClient to real customers. Do you want to train your end users to look out for these ten "gotchas" (and the 49 others)?
Burning a CD using third-party applications may fail on Windows 7
Workaround: Please use the Microsoft Windows 7 CD-burning utility
Internal speaker may continue to emit sound when speakers are plugged in
Workaround: None available.
Issue: The integrated SD card reader available on some platforms presents itself as a PCI device, and is currently not supported for access by guest VMs.
Workaround: Use a USB SD card reader, if possible.
Windows 7 volume control behaves incorrectly at very low values
Workaround: Use higher volume settings or mute.
Cannot set password using localized characters
Issue: Setting a password via the system settings area of XenClient, does not allow input of localized characters.
Workaround: None available.
Hot-unplug from laptop dock causes screen to go blank, requiring a reboot
Issue: Dell E4310 with a 3D Graphics Support-enabled VM can become unresponsive if hotunplugged from a laptop dock
Workaround: Do not hot-unplug a Dell E4310.
Audio suffers when XenClient has heavy load on CPU
Workaround: None available.
Secure Application Sharing application may fail to launch on Application Subscribing VM
Issue: Intermittently a Secure Application Sharing application may fail to launch in the Application Subscribing VM, with no error message.
Workaround: None available.
Unplugging a USB audio device while it is in use on an XP VM can cause the VM to hang
Issue: Unplugging a USB audio device, such as a set of USB headphones while it is actively in use can cause an XP VM to hang.
Workaround: Ensure that the USB audio device is not currently is use (for example, currently playing music) and unplug the device using the standard XP mechanism.
Accessing a re-writeable optical device that is being written to in one VM from a different VM can trigger a BSOD
Issue: Attempting to read from an optical device that is being written to from a different VM can cause an error to be thrown. Subsequently attempting to write to the re-writeable optical device can trigger a BSOD.
Workaround: Ensure that the writing session in one VM has closed before accessing the optical disk in another VM.
Are your users ready for XenClient 1.0?
Ok, so who's ready for this? Who's going to start deploying it to customers and end users? Honestly I can't believe that Citrix is releasing this as a real product.. I guess this way their marketing people can go nuts telling everyone how awesome it is while in real life it's still a beta-quality product.
And actually I should point out that I still love the concept of XenClient. I'm not frustrated with the idea of it. I'm frustrated that Citrix is selling software that's not ready. Now folks are going to try this, see that it sucks, and be set back another five years before we can get them to try client hypervisors again.
Oh, and by the way, how brilliant does VMware's cancel-type-1-replace-with-type-2 strategy seem now?