Friday, March 16, 2007

Virtualization in Education

I've had the opportunity to talk about virtualization in a few different contexts lately and so I thought I'd put together a post on it.

What is Virtualization?
Well, that depends a little on who you are talking to. The most popular notion of virtualization is virtual machines. This means running another computer as a software instance on top of another operating system. An example would be VMWare Workstation. In this instance you may have a Windows XP computer running a "virtualized SLED 10" system. Thus, you could be running programs for both operating systems at the same time on the same hardware.

Taking that to another level, many people (such as Whitfield) use virtualization for server consolidation. We had about 8 servers coming to the end of their lease life. Thus, rather than replace them with 8 new pieces of server hardware, we bought two beefy blade servers for our IBM BladeCenter and bought VMWare ESX virtual server software. We then used a utility to automatically migrate our physical servers to virtual servers. Now, we have two pretty beefy physical servers which are running about 16 different virtual servers. Each of these servers is configured pretty much as they were before. We use Remote Desktop to access and control the servers and they function just as they would if they were on physical pieces of server hardware. However, in addition to all of the tools offered by the server operating systems themselves, VMWare offers additional tools to diagnose and control the system resources being used by these servers, helping us to tune them to a higher degree.

Another form of virtualization is application virtualization. This allows you to run applications on a system as though they are on another system. Mac does this with OS9 application being run on OSX systems. Linux does this when running Windows programs with WINE. Also, some people refer to hosted applications, such as Citrix as virtualized applications. In this case, programs such as Microsoft Word, actually run on a Windows server but appear to the user as though they are running on his or her Linux laptop. This is how we run Windows programs in our Linux Laptop Program.

What's the hullabaloo about Virtualization?
(Thank goodness blogs don't have editors that make me cut out words like hullabaloo)
People are excited about virtualization and there are reasons for this. Virtualization can save a lot of money. Effectively, you only need disk, rather than hardware, to run applications and operating systems. Disk space costs a lot less and you probably already have disk space you're not using! Another reason people are happy about virtualization is that it removes many of the traditional obstacles of IT. Now you can run Windows on Mac hardware, without buying and carrying two computers. You can run Windows applications from a Mac or Windows machine. You can also manage virtual systems quite easily with management tools. Many of these management tools give you low or no cost management of systems that would be unavailable or cost prohibitive on physical machines.

Virtual Desktop Initiative
This is perhaps the coolest combination of virtualization technologies. Though I have seen a few different applications of virtual desktop initiatives, I will describe one I've seen being done by a major financial services company.

When a new employee joins the company, they go to the "request a workstation" web page from the low cost thin terminal sitting at their desk. They are prompted to answer a series of questions through a webified wizard. It asks questions such as what operating system do you want, what department are you in, etc. Then, based off the user's department and request, the user is provisioned a virtual desktop that appears on their screen as though it is installed locally. This system is created in about 5 minutes from templates that already exist. They also are provisioned all of their applications via Citrix right on the machine.

Users have lots of control over these machines, depending on their role in the organization. Many are allowed to install software, change desktop settings, etc. The reason this organization offers these increased powers is because they can easily restore the computers back the a previous snapshot which is grabbed by default. What's more is that users can go home and use a web browser on their personal home computer to access the entire virtual computer and work just as though they were sitting at their desk.

OK. This post is getting long so I will stop here. I will post again soon on the up-sides and downsides of virtual desktops in education, particularly when compared to terminal services.

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