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.
recovery
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?
From Startup Manager to Internet Recovery on Intel Macs, and how to engage each of those in an M1 Mac. With comprehensive diagrams.
Unlike Intel Macs, M1 models always start booting from internal SSD, and can only offer full Recovery from there too. This has benefits, and some drawbacks too.
M1 Macs don’t use that warren of startup key combinations, but a logical structure of choices, mostly when starting up in Recovery Mode. Here are the full details.
First update it to 11.0.1. Here are details of the problems which can arise and how to solve them, from unenrolling from betas to using Configurator to Revive an M1 Mac.
When you go to perform a clean re-install of Catalina, what should you do? Which volume(s) to erase or delete, and how to fix problems?
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