Booting an M1 Mac from an external disk: it is possible
Booting an M1 Mac from an external disk: it is possible Last week I described how I had been unable to get either of my M1 Macs to start up from an external disk. Thanks to many comments but no real clues, I’ve now been able to solve this, and here explain how you can do this too. Reliably. You’ll need the following: an M1 Mac; if you haven’t got one yet, I’m afraid it’s far too late for Christmas; a Thunderbolt 3 SSD, such as a Samsung X5, freshly formatted in APFS (unencrypted) and connected to one of your M1 Mac’s Thunderbolt ports; if you only have SATA SSDs which connect v...
Source: eclecticlight.co