macOS 11.4 brought major changes to the way M1 Macs handle external bootable disks. This explains how this works during the boot process.
recovery
There’s 1 True Recovery, Fallback Recovery and one other recovery mode. Disambiguation, explanation and how this changed in macOS 11.4.
One command in Terminal which instantly disables any support, and why you can’t (yet) boot your M1 Mac in Linux.
My M1 Mac mini was stuck trying to start up. Its power light was on, but there was no video output, and to all intents it was dead.
How an M1 Mac can start up from an external bootable disk, and how that can fail. All about boot security policy, and how that’s applied.
How changing a volume’s boot policy can let you boot in older macOS, and update, if you wish. For anyone who uses external bootable disks with an M1 Mac.
Created when you update macOS, its Fallback Recovery OS is made from the previous Recovery OS. Here’s how to check whether it’s available on your M1 Mac.
Apple has revealed the hidden Fallback Recovery OS mode available on M1 Macs. How to enter and use it, and why it’s another big plus.
How you might be able to update an external bootable disk, errors you can encounter, and how can you use 1 True Recovery?
macOS updates sometimes don’t work out right. What can you do to revert to the previous release? Did I hear you mention snapshots?
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