Apple precede the APFS ( Apple Filing System ) file cabinet organization protocol in macOS Sierra . It ’s now the required data formatting for macOS , but it took a while to transition from the former implementation of the HFS+ ( Hierarchical File System Plus ) format . Even during the transition , Apple keep the bequest standard HFS+ viable for backward compatibility . ( It ’s called “ Mac OS Extended format ( Journaled ) ” in Disk Utility . ) Macs persist versions of macOS as recent as Sonoma can still read HFS+ formatted volumes , even if you ca n’t boot a Mac from an HFS+ bulk go with macOS 10.14 Mojave .

Apple also let HFS+ hover for Time Machine backup . It take several releases of APFS - enable macOS before Apple adapted APFS to encompassa particular Time Machine backup book type . ( That happen in macOS 10.13 Big Sur . )

The fellowship provide no transition for exist Time Machine archive , however . While you may reformat a stock strong saucer drive ( HDD ) or SSD that was set up with HFS+ to employ APFS or else , the reformat is destructive . You ca n’t elevate a Time Machine book , nor can you copy a Time Machine backup with its archive format intact from an HFS+ volume to an APFS volume and go on backing up to it .

How to switch a Time Machine drive from HFS+ to APFS

If you ’ve been using Time Machine with an HFS+ campaign ( something still allowed with Sonoma ) , how do you transition to APFS , have it off that Apple will probably eliminate Time Machine on HFS+ in some future vent of macOS ? ( Apple typically give at least two years ’ admonition , sometimes longer , for major changes that involve filesystems and or security features . )

The two scheme you have are :

A substantial carefulness : Always have a couple layers of musical accompaniment . I perform a nightly clone of my inauguration drive to an external volume , keep Time Machine running endlessly , and also back up my documents to a good on-line storage company . check that you have at least one full backup before you make any significant modification , but two are ideal .

The “ uncontaminating slating ” strategy above has the advantage of toll and ease . But you lose all premature versions of any filing cabinet and any deleted files that have n’t yet been vomit . The “ retire and replace ” approaching give you a deep judiciary and an extra level of trade protection for as long as that older private road stay on in working consideration and Apple does n’t abandon HFS+ . Even after Apple moves on , you ’d be able to mount up and get at an HFS+ Time Machine volume on a Mac with an older version of macOS , of course .

This Mac 911 clause is in response to a question put in by Macworld reader Eric .

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