Install macOS in Recovery can only install one version, which probably isn’t the one you want. How can you get an earlier version installed, then?
Big Sur
How useful is the traditional panacea of re-installing macOS in Big Sur? And is it worth maintaining an external recovery disk to deal with problems?
Content Caching server originated in 2005, as a feature in Mac OS X Server, which sold Xserves. Time Machine came in 2007, to support Time Capsules. Those legacies are so different, though.
Details of how the Content Caching server handles a cache macOS security data update, and both client and server handle an App Store update.
Using Activity Monitor and command tools to assess performance of a content caching server, and diagnosing problems from the log.
Big Sur updates have far exceeded those of Mojave or Catalina, and are set to total well over 40 GB. Prospects for security updates are no better, with a high carbon footprint.
Snapshots are designed to make it easy to roll back to a previous state. Why then can’t you use a snapshot to roll back to an earlier version of Big Sur?
Recovery on an M1 Mac runs from its own container, which should improve its robustness. It has one simple entry point, and offers a full range of facilities in an integrated environment. It’s a big step forward.
One command, bless, used to do it all, copying boot.efi to the right place and declaring the volume bootable in its header. Where are we with Big Sur and M1 Macs?
How your M1 Mac starts up in the Recovery mode of your choice, or when it decides you need to take a trip to Recovery to fix an issue.
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