Building a great VDI ready Windows

VDI is getting more attention everyday. Companies are transforming their Windows XP installations into VDI desktops. We all aim to get as many XP installations on an ESX host. When preparing my testlab I was not amused to see that XP after a default install, without any fancy stuff is quite memory hungry. Without any SP or updates, XP is running quite low on memory, but once you install SP2 and a number of updates, your default install will take much more memory. For a VDI environment it would be great if we could make XP a little less memory consuming.

Using nLite you can easily build XP installations that are much smaller than your default install, not only in RAM usage but also in disk usage. With nLite you walk through a wizzard that helps you to disable unnecessary services, remove unwanted programs or accessories and remove unneeded drivers. Many drivers included in XP are not needed if you’re working with VDI desktops. The hardware will never change, apart from a VMware Tools update now and then. So, we can leave out all the drivers for other devices, except for USB. Leave USB in to be able to connect external devices into your VDI desktop.

 

Not only can you disable drivers, you can also included new drivers. To include the VMware drivers, open the windows.iso file you can find on your esx host in the /vmimages/tools-images directory. Extract the contents to a folder on your harddisk. In nLite you can now add the drivers from the “program files\VMware\VMware Tools\Drivers” directory. nLite scans the folders and lets you select the correct driver to include. For the VMware SCSI driver choose text-mode if asked. Remember, this only installs the drivers, not the VMware Tools !!! I bet it is possible to also include them in the image, but I haven’t researched this yet. So don’t forget to install them afterwards.

When working with nLite you have to think very carefully what the user has to be able to do with his VDI desktop. You want to disable as many unneeded parts as possible, but disabling one too many can make your desktop useless. After creating a new XP ISO with nLite be sure to do some real good testing if everything your user would want to do is also possible.

Playing with nLite eventually gave me a XP VDI desktop that runs with SP2 and only has 60Mb RAM in use, but this is only a first step, because the desktop can only surf the internet and isn’t running stuff like Office or Anti-Virus. There is still a long road ahead before I have the most optimal combination of enabling and disabling services, applications, drivers, etc. but I know now that nLite is a very valluable tool to build your VDI structure.

nLite is freeware and can be found here:  http://www.nliteos.com. nLite supports Windows 2000, XP x86/x64 and Windows 2003 x86/x64 in all languages. It needs  .Net FrameWork 2.0 in order to run.

For Vista there is vLite. Which can be found here: http://www.vlite.net/.