When trouble strikes a disk image, macOS normally refuses to accept and mount it. This details how to use hdiutil to attach the image as a device so it can be repaired by fsck_apfs.
Disk Utility
The new ASIF disk image type is now 18 months old. How well does it perform? Is it as good as claimed? It all depends on whether you want to use encryption.
They come in a multitude of formats and variants, and are used throughout macOS and apps. How do you use them, and what should be wary of?
Should you attempt a repair in Recovery mode? Is it just a warning? How to identify the file or folder with a problem, and what to do to fix or prevent it from recurring.
Safe mode is claimed to do 3 things: block 3rd party extensions, clear caches, and check your startup disk. But what disk checks does it really make, and how are they different?
How to erase just the Data volume, the whole Boot Volume Group, all volume’s in the Mac’s visible container, or the entire internal SSD.
Fundamentally simple: a preserved copy of a volume at a moment in time. How its size can only increase with time, how they’re managed, what they’re used for, and the tools for using them.
It was notorious for its crashes and reporting discrepancies, but now it’s incorporated in System Settings it’s more reliable and helpful. But there’s still the problem of System Data.
First Aid in Disk Utility, or running fsck_apfs in Terminal, return warnings or errors on one of your Mac’s volumes. Here’s what to do next.
Why upgrading to Tahoe shouldn’t consume the last free space on your Mac’s SSD, and once it has settled should use little more than currently. How to clear out old snapshots and reduce System Data.
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