There are substantial differences in the structure of the internal disks in macOS, iPadOS and iOS, as shown here. And there are at least 24 cryptexes now used to support AI.
Startup Disk
Which versions of macOS can you ‘dual boot’, should you install them all on the internal SSD, or is a bootable external disk better, and when would you need to virtualise?
Simply having a boot volume group with a System snapshot in it won’t get your Mac to start up from that disk, particularly if it’s an Apple silicon model. Some details.
This has changed greatly over the last few versions of macOS, and differs between different types of Mac. Here’s an outline.
When a startup disk is running short of space, needs a good clean up, or isn’t quite right, it’s tempting to try surgery. Here’s what you can get away with.
Monterey changes the way that Recovery works on M1 Macs, making them more like Intel Macs by using a paired Recovery volume. But that could spell trouble.
Creating the external bootable SSD, downgrading security and allowing kexts, then trying to install a kext on an external drive which must be ejected.
Assigning ownership to an external bootable disk doesn’t always work in Recovery mode on an M1 Mac. But there’s an easy workaround.
M1 Macs are different, as they always start booting from their internal SSD. Basic configurations are simple, reliable with well-established disaster recovery methods.
Full macOS installers come in different presentations according to how they’re obtained. Explained here are what’s in an installer app, and how a bootable installer disk works.
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