Want to create a bootable external disk for your M1 Mac? Here’s how to do it in full detail, from erasing the volumes through to how to remove it safely.
disk
Introduced in Mac OS X 10.7, it remained an HFS+ partition until High Sierra. With Mojave, it became an APFS volume, except for M1 Macs.
Turning the data blocks into files and directories, these have common functions and additional features which can give rise to tricky problems.
Making an external bootable SSD for an M1 Mac has proved tricky. Has this changed in macOS 11.2? If you’ve already got 11.1 running on one, how do you update it to 11.2?
Disk structure diagrammed for comparison, from the partition table, to HFS+ and APFS volumes, with further references.
What you need to know about the APFS file system, its containers and volumes, so you can understand errors and how to repair them.
What you need to know about the HFS+ file system, so you can understand error reports and how to repair it using Disk Utility and other tools.
What you need to know about disk formatting using the GUID Partition Table (GPT) to understand its problems and how to repair it.
Apple says that if you run First Aid on a disk, each of its volumes is checked too. Is that really true?
What do you know about the hidden and unmounted EFI partition on all the disks you use with your Mac? It could be very important.
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