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” workstationsHard to support, no standard softwareHard to manage configuration, no telling

what’s installedRisk of data loss, company data not safe

Businesses need to “prove” compliance with IT security policies

Shared Services

Many users share one machineA user can “run away” with RAM or CPUDifferent 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 machineMachines can be spawned on demand from

a golden imageDesktop 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 clientsIf 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 imageBare 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 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 Alike 3.0 Unported License. To view a copy of this license, visit http://creativecommons.org/licenses/by-nc-sa/3.0/ or send a letter to Creative Commons, 171 Second Street, Suite 300, San Francisco, California, 94105, USA