The art and science of OS X system upgrades
Since 10.2 (or was it 10.1?), we Mac users have had to make a choice when it comes to major ("dot release") OS X releases: how will we upgrade? In its current incarnation, the OS X installer offers three options:
- Upgrade Install: The easiest option for users, this simply patches the necessary bits of the system and bundled applications to migrate from the current OS to the new release.
- Archive and Install: The installer moves the entire current system, Users folders and all, into a Previous System folder, and then installs a new copy from scratch. You can optionally migrate over your Users folder to ease the transition.
- Erase and Install: The "wipe the slate clean" approach. Your hard drive is erased, a new system is installed, and you start over from scratch.
Which method to use is seemingly a matter of great debate. Apple has a good overview available, too, with a brief description of each option.
Having just recently started (note that it's not yet completed) migrating my primary boot drive to 10.4, read on for my thoughts on upgrade strategies, the strengths and weaknesses of each of these methods, and which I prefer (and why).