12 Advantages of Virtualized Desktops
Author: Mike Lovell
Date: May 15, 2009
Note:
While I tried to write this article for anyone with a slightly enhanced knowledge of computers, an understanding of Virtualization and Virtual Machines would help with the material in this article. There are many, many resources on the internet to find out more. I would recommend Anandtech's Introduction to Virtualization as a good starting point.
If I've said it once... I've said it a thousand times; Green computing is not just about becoming more environmentally friendly. It is also about using Green Computing technologies that can benefit an organization's Information Technology (IT) and solve real problems. Using virtualized desktops can save on hardware, software, and energy, but it can also do so much more.
Desktops are the computers an organization's employees use every day. Desktop virtualization is the idea of taking each desktop in your office and running it on a Virtual Machine (VM). This allows you to move desktop computers to more centralized and powerful servers. To use these machines, employees remotely connect to them from another computer. While this might sound like a more complicated setup at first; nothing could be further from the truth. This article hopes to shed some light on the advantages of such an IT infrastructure and why your IT department and employees are going to love it.
One image to rule them all
Pretty much every organization with more than one computer has this problem; not all of your computers are the same. Even computers that look exactly the same can have wildly different hardware. A smart IT manager will develop a separate hard drive image for each type of machine so they can easily deploy or reformat a machine. But keeping all of these images up to date and organized can be a real headache.
The beauty of virtual machines is that you no longer need to worry about keeping different images for different hardware. All of the virtualized hardware is the same on every machine, so only one image is required. All of the settings and applications your organization needs for every machine can be setup and kept up to date by IT staff in one place.
A better way to backup your desktops
For those that are not completely familiar with virtual machines, this would be a great place to explain the idea of a snapshot. Making a backup of a virtual machine is a little different than backing up a regular computer. With conventional backup methods, one would save the hard drive data and settings of a computer. With a VM, since you are emulating the machine in software, you save an instance of that computer. Basically, you are saving the entire computer. So, if something goes wrong, you can revert back to exactly the way that machine was before. And, to put icing on the cake, these snapshots take mere seconds to create and seconds to revert back to.
It is worth noting that in order to ensure that data is not lost in a revert, organizations should get use to no longer saving any documents or data on individual desktops. A centralized storage setup is a must in a virtualized desktop environment.
Rapid deployment of Desktops
Since you have one image that is used for all desktops, deployment of a new desktop becomes quick and easy. All the IT staff has to do is create a new virtual machine, install or clone the image, and setup a computer to remotely connect. Remote connection software can consist of an application include with the Operating System (OS) of the connecting computer (like Remote Desktop Connection that comes with Windows) or an embedded OS built into a thinclient. I have even built systems that boot a client from the network. This allows you to setup any computer in less than a minute (you just have to set the computer to boot from the network). The computer does not even need to have a hard drive installed.
No more update worries or viruses
Now that you have this rapid deployment and only one image to deal with, the IT staff's updating and virus/malware protecting duties become a lot easier. When an update to your organization's operating system (like a Windows update) is released, your IT staff just has to update it on the main image and redeploy. So, the next time your users log into their desktops, the updates are already there.
In the same vein, viruses and malware become almost trivial problems in a virtualized desktop environment. If a user gets a malicious piece of software on their computer, it only takes seconds to revert back to a snapshot. A virtualized desktop environment creates a situation in which the IT manager does not have to worry about what a user does on their computer.
Remotely Connect to your computer from anywhere
Connecting to your virtual desktop from in your office is pretty simple. But, what if you want to connect to it from another computer on your network? No big deal; just move to another place on your network and log in. Now you have all of your applications, settings, bookmarks... essentially your entire computer anywhere in the office. It doesn't make any difference which computer you use; you are still using the same virtual machine.
Now let us take that idea one step further. What if you wanted to connect to your computer outside the office? You can do that as well! You can connect to your office computer at home, at a cafe, on a plane... anywhere with an internet connection. Your employees will have the same computer with the same computing experience wherever they go. Even if you will not have an internet connection the entire time, some VM client software now offers offline mode and sync back up to your VM once you get back to an internet connection.
Use computers that are less powerful
Now that all your computing power is determined by your virtual machine running on a server somewhere else, it's time to look at what that means for your physical computer. Your physical desktop workstation has been reduced to a glorified window to your virtual desktop. It has little to do with what is showing up on the screen because all the real work is being done on your server.
This allows use to use less powerful computers to act as this window. Lower powered computers can mean several things. They can be thinclient computers, low energy computers (like netbooks or nettops), and even older hardware. The computer that you are using to connect doesn't really matter. This fact applies to the next three points.
Buy cheaper computers
Because your computers at the desktop level no longer need to be speed demons, the computers your organization will buy do not need to be powerful to run the latest software. In fact, if you want to upgrade all of the computers in your network, you don't have to touch the physical desktop computers. You can, essentially, just upgrade the servers.
Use computers longer
Now that your computers don't have to be as powerful, you can keep older computers around longer. In most organizations, a 3 to 5 year lifecycle is common for computers. In a virtualized desktop environment, it is typical for workstations (especially thinclients with less mechanical parts) to have a 8 to 10 year lifespan. The reduced impact to your hardware costs and the environment are obvious and significant.
Use less energy
It would be odd for a website revolving around Green IT to not mention environmental impact. The energy savings from switching to this kind of IT infrastructure and using low energy computers is huge (as much as 80%). However, it would not be recommended to throw away all of your computers and switch right away. This would be neither cost effective or green. This kind of infrastructure change is part of a long term plan and it is recommended you switch to lower energy computers as you replace your current computers.
Next to zero downtime
First, we will look at how virtualized desktops cut down on downtime at the user level. Let's just say that your physical computer goes down, for whatever reason. Turn it off, switch computers (or have it replaced), and log back in. This gives your IT staff the freedom to take your computer to their offices to fix it. Now you can continue on with your work instead of waiting. Even in the case of catastrophic computer failure, you will only receive a few minutes of interruption.
On the server side of the equation, it is a little different. Someone asked me at my last Green IT presentation, "What happens when your server goes down?". This is a great question. We don't want to be left with no one being able to do any work.
There are a few factors to look at in this answer. The first is to look at how server hardware is designed. Superior cooling, high-end power supplies, and redundant storage are just some parts of servers that are built to run 24 hours a day, seven days a week, 365 days a year. Unlike your traditional desktop computer, they are mission critical devices. Running desktops on such machines controlled by an adept IT staff is much more reliable than any traditional desktop computer.
Another factor is the possible small code base of virtualization software (aka. the hypervisor). To give some perspective, a typical operating system (like Windows, Linux, or OSX) is built from millions of lines of code. When booted, these OSs run a lot of processes, have to deal with a lot of drivers and applications, and generally have a lot of things that can go wrong. However, a "bare metal" hypervisor (VM software that runs directly on the computer hardware) is very small, in comparison. Where current versions of Windows take gigabytes of space to install, many hypervisor's space requirements can be measured in megabytes (VMware ESXi is about a 32MB install). With such a small footprint, there is less that can go wrong with these hypervisors making their reliability extremely high. However, even if you are not running a "bare-metal" hypervisor, VMs running on top of an OS are considered to be incredibly reliable.
It is also important to note that each virtual desktop running on a server is separate and isolated from the rest. Therefore, if one becomes slowed down or has a serious problem, it will not affect the other virtual machines on the server.
Now, if those factors don't reassure you, there are even further steps that your IT can and, most likely, will take. Virtualized desktop setups are not designed to only have one server. Therefore, if one server goes down, your users can log into another server and get back to their work in just a few moments. To sweeten this type of setup even more, virtualization software infrastructures (like VMware's View) have included vitual machine management servers. These management servers provide a great deal of features. One feature is that if one server goes down, the management server will boot the virtual machines on another server and connect users to it automatically. All the end user will see is a pause of only a few seconds. They will then be able to continue using their computer as if nothing happened.
Fix more problems remotely
Connecting to client computers and fixing problems remotely through remote desktop, VNC, or services like logmein are not new to IT managers. However, it is worth noting that virtualized software and hardware can be even further controlled remotely. For example, if a user had only 1GB of RAM assigned to their VM, but they want to run a piece of software that worked better with 2GB of RAM. Well, your IT staff could actually assign a desktop with more RAM remotely. It is not a common scenario, but upgrading RAM from a distance is very possible in a virtualized desktop environment.
Better data security
It is estimated that losing a laptop can cost an organization almost $50,000. The security risk and loss of precious data can hurt any organization. As I said before, virtualized desktops can allow a user to connect to their computer from anywhere, but this is not the only advantage for the employee that is away from the office. Since their VM is running on a server located within the organization's network, none of the data or storage is located on an employee's physical hard drive. In a theft scenario, as soon as the thief closes the laptop (it would seem unlikely that a thief would run away with an open laptop!) the user is logged out of the organization's network and all data is safe and secure. If proper login security protocols are followed, there would be nothing worry about.
In the near future, a virtualized desktop infrastructure will become commonplace for organizations large and small. But it is important that IT departments begin planning and implementing now. A careful IT strategy that includes virtualized desktops will ensure an organization has a smooth transition to better IT that will greatly cut down on costs and headaches while becoming more environmentally friendly.
