Which of the external disks tested can be used to boot from? Do they work reliably with Secure Boot? Could you boot from an external hard disk?
startup
How to use an M1 Mac’s Recovery system to boot in Safe mode, boot from another disk, and use its other important features. With a map.
Once the kernel takes over from iBoot, there’s a lot of hardware to get running before the SSV can be properly validation, and kernel extensions loaded.
Sometimes known as iBoot1 and iBoot2, they start work with the LocalPolicy for the intended boot volume, validating its vital components.
Understanding each of the four stages in the Secure Booting of an M1 Mac. These are summarised in diagram available here.
There’s a fundamental difference in the way that Intel and M1 Macs store and load their ‘firmware’, which enables the M1 Mac to load and run difference versions of iBoot.
This article has now been extensively corrected and modified.
Odd things can lead to some Macs starting up or waking up spontaneously. Here’s one solution to those mysteries.
Four popular and straightforward ways to set your Mac to run an app or other software when it starts up. Includes AppleScript code.
Now lists the time of the start of all boots in the last 24 hours, and helps you with Unicode normalization problems.
The Eclectic Light Company 