With a new version of Xcode, I knew that my network backup would take several hours. Then, as it neared its conclusion, disaster struck: the router reset itself and the network share vanished.
Provided it doesn’t have to back up large folders containing many small files, Time Machine backing up to APFS on a network share works well.
The first full backup is performed as a manual backup, and largely occurs in file-by-file copying from source to the backup store. It is more efficient than to HFS+, but differences could be less than 10%.
Does Big Sur’s Time Machine preserve sparse files and clones when backing up to APFS volumes?
It’s common to want or have to change either the source or destination disk for backups. How well does Time Machine to APFS cope with that?
Given their very different structure, backups on APFS disks shouldn’t require routine maintenance. Checking and repair is performed using Disk Utility.
Unlike HFS+ backups, those on APFS volumes look different depending on how you try to access them. What you see in the Finder is an illusion not available to other apps.
Analysis of the phases of backing up to APFS shows the many similarities with that to HFS+. Crucial differences arise from the use of snapshots as backups.
A blow-by-blow account of what happens when Time Machine in Big Sur performs an automated backup to an APFS volume.
How each of the three different backup schemes used by Time Machine has worked, and how snapshots can work as backups.