The other week it was suggested to me that if/when we upgrade our Macs at school to Lion, building a fresh system image and then rolling that out is a good idea as it ensures computers are as stable as possible. It sounds like a bit of a job, and definitely a Summer Holiday job, but it does make sense as all manner of cruft can collect on a system image when it gets upgraded and then copied from one computer to another.
In anticipation of this, I decided to completely reinstall my new personal MacBook Air. I had been copying my accounts between machines since a 2004 12″ PowerBook (via a Black and then Aluminium MacBooks), and doing in-place upgrades from 10.3 to 10.7 (Panther, Tiger, Leopard, Snow Leopard, Lion!) so there undoubtedly was a lot of cruft!
Once I’d figured out how, doing a fresh install with Lion wasn’t too hard. Simply hold command+R when booting up to access the recovery partition, use Disk Utility to wipe the hard drive and then click the download and reinstall Lion button. Simples!
The Mac App Store then provided me with most of my software and all the iLife 11 titles and my Time Machine backup gave me back all my files. This second part wasn’t quite as easy as expected as restoring documents kept resulting in permissions errors. The solution to this was to use Migration Assistant to copy my old account onto the Mac under a new temporary name, log onto it and then move all the required files onto /Users/Shared. I could then log in onto my new account, copy the files across from shared and then delete the temporary account.
The upshot of all this is that I have regained an extra 30GB of space on my hard drive! Not bad… It also answers my question of where iLife apps that have been downloaded from the App Store keep their loops/audio samples. It seems that iPhoto and iMovie now keep everything within the application bundle, whereas GarageBand downloads 1GB of loops into /Library when you first open it if they’re not already there.
So hopefully all this will come in handy when creating a master image at school!