Greg Porter, MCITP: EA, Cal Poly
October 17, 2010
What is a desktop virtualization?

Depends on the marketing droid you are
talking to – there’s a lot of hype.

Desktop virtualization… separates a…
desktop environment from a physical
machine using a client–server model of
computing. The model stores the resulting
"virtualized" desktop on a remote central
server… thus, when users work from their
remote desktop client, all of the programs,
applications, processes, and data used are
kept and run centrally. (Wikipedia)
This isn’t new…
This was the ORIGINAL model of
computing - a “terminal” (character
based display device) attached to a
remote server
 X Windows (Unix) based solutions for
doing this have been around for 20+
years

Why the hype now?

Desktops are out of control, users load
and run whatever they like on “their”
workstations
 Hard to support, no standard software
 Hard to manage configuration, no telling
what’s installed
 Risk of data loss, company data not safe

Businesses need to “prove” compliance
with IT security policies
Shared Services

Many users share one machine
 A user can “run away” with RAM or CPU
 Different users may need different apps that
conflict with each other
Can be relatively simple to deploy
 Sun Global Desktop, Citrix XenApp,
Windows Terminal Services

Shared Services
(a la Terminal Services, XenApp)
Desktop Virtualization

Similar to shared services but:
 Each user gets “their own” virtual machine
 Machines can be spawned on demand from
a golden image
 Desktop controller server manages user
connections, VM power states, load
balancing
 Users CAN share a machine if appropriate

Citrix XenDesktop, VMware View
Desktop Virtualization
Production
Example –
Vmware
View
Achilles has a heel
All of these schemes require a display
device – you need a desktop to see your
desktop
 Business would like to reuse their existing
PC’s until they die – repurposed as thin
clients

 If you reuse PC’s, now you have to manage the
desktop machines you already have PLUS the
virtualization infrastructure

End users in general don’t like the idea of
thin clients – you are taking “their” machine
away
You could re-use your PC’s

Make and deploy a stripped down OS
image
 Bare minimum Windows + proper client
software (ICA client for Citrix, View client for
VMware)
Defer replacement for now, save a little
money in the short term
 Double the work, you have to manage
the real workstations, plus the virtual
workstations

You could buy actual thin clients





A couple of hundred dollars a piece, not
that much cheaper than an entry level
workstation
Run their OS from firmware, no moving
parts
Most have some firmware update
management scheme
Easy to manage than repurposed PC’s
Get the “right” one for your solution
 Make sure the ones you buy natively connect to
your solution. ICA clients for Citrix, View clients
for VMware, etc.
Lessons Learned



Vendors wildly overstate the savings
Dramatically increases complexity on the server
side, especially if business has little existing
experience with virtualization
End users typically hate thin clients
 To be accepted, the “new” solution has to be dramatically
better than the old desktops
 Someone suggested stuffing the thin clients into an empty
desktop case…


Once they use it, end users *REALLY* like having
their desktops available from anywhere
They also *REALLY* like persistent state, where they
can disconnect, then reconnect, and continue where
they left off (a la Session Broker, etc.)
Here’s something truly new –
On Demand Desktop Streaming

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


Originally made by Ardence, licensed by
Dell (ODDS), now part of Citrix
XenDesktop (Citrix Provisioning Server)
Boot many PC’s from one central image
PC’s don’t need a hard drive
Can display a menu of boot images to pick
from - Linux, Windows, etc.
You don’t need a desktop to see a desktop
Ardence demonstration
Head to head with SATA at Univ. of Neb.
© 2010 by Gregory L. Porter, glporter@calpoly.edu. This work is licensed under the Creative Commons Attribution-Noncommercial-Share
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