Michael Niehaus has a new post up over on his blog.
I’ve always been a fan of the thinnest image possible. Taking that to an extreme, that means using the original image straight off the Microsoft media. But over time if you did this you’d find that the time required to apply patches to that image becomes unmanageable. (Case in point: I started up a new laptop for the first time with an OEM-installed image that had hooks to require all patches be applied before first logon. It took three hours for that to happen.)
I’ve also been a fan of doing “just in time” patching, which is something that MDT can do too: Instead of patching the image in advance, you can inject updates offline after the image has been applied to the disk but before it boots for the first time. That does often improve the time required, but it doesn’t eliminate it – it adds time when initially injecting the updates offline, and then more time on first boot as the “online actions” for those “offline patches” are completed (you’ll see the messages on the screen during the first boot showing a percentage complete while this is happening).
So reading between the lines, that means I would suggest always creating your own master image containing at least all the current service packs and patches. (Don’t try to install the OS service pack yourself – just download “slipstreamed” media from the Microsoft licensing website, as that’s the ultimate time-saving technique.) So how should you do this? Well, there are a few ways:
- Mount the existing WIM image and just inject the updates offline with DISM. This is certainly doable, but there are three challenges:
- The online actions for these updates will still take some time
- It introduces a “human touch” into the process, unless you go through the effort of automating this to make it a repeatable process.
- It only works for operating system updates.
- Build a new image and install all the updates into that image before sysprepping and capturing the image using a completely automated process. This is my preferred approach, because it’s a consistent process for any other type of update being made to the image.
Not surprisingly, MDT 2010 Lite Touch provides a way to implement my preferred method above – and actually multiple methods that can be used. Let’s go through those methods.