APFS changes affect Time Machine in macOS Big Sur, encrypted drives in iOS 14

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in macOS
Apple is increasing its support for APFS on its computing platforms, bringing the ability to use Time Machine with an APFS-formatted disk to macOS Big Sur, while enabling the ability to view external drives using encrypted APFS in iOS and iPadOS 14.

Time Machine in macOS
Time Machine in macOS


Introduced in 2016, APFS is Apple's forward-thinking file system that it uses across practically its entire device ecosystem. With the introduction of macOS Big Sur, iOS 14, and iPadOS 14, Apple will be making it even more useful for users, by adding support for APFS in a few new areas.

On macOS Big Sur, Apple is finally bringing the ability to use an APFS-formatted drive with Time Machine, 9to5Mac reports. With macOS Catalina and earlier releases, users were able to back up to an HFS+-formatted disk but not an APFS-formatted version, with macOS offering to reformat the drive to HFS+.

Under Big Sur, users will be able to back up directly to an APFS-formatted drive, eliminating the need to reformat any disks.

Encrypted Drives in iOS 14

For iOS 14 and iPadOS 14, Apple has plugged a hole for external drive support for one specific use case: APFS encrypted drives. While it is currently possible to view external drives in a number of common formats from an iPhone or iPad, it only works for non-encrypted drives, with encrypted drives being unreadable by the mobile devices.

On connecting an encrypted APFS drive to iOS 14 or iPadOS 14, the drive will appear on the updated Sidebar, with a selection of the drive bringing up a password prompt to decrypt it.

The added support for encrypted drives will only work for APFS-formatted drives, which may still be a limiting factor for some users in a multi-platform environment.
dewme

Comments

  • Reply 1 of 12
    zeroIDzeroID Posts: 13member
    This is what I wish, but....

    Is this valid also for encrypted DMG sparsbundle containers, or only for physical disks ???
    An encrypted DMG sparsbundle container is a drive in macOS, is this valid also for iOS & iPadOS?
    watto_cobra
  • Reply 2 of 12
    rob53rob53 Posts: 3,241member
    What about formatting external RAID HDD as APFS? OWC’s SoftRaid is waiting for Big Sur to make this happen. My RAID can’t be used to backup my Catalina APFS volumes. 
    ivanhwatto_cobra
  • Reply 3 of 12
    neilmneilm Posts: 985member
    So unless Apple has re-engineered Time Machine, they presumably must have updated APFS to support hard links. Anyone know?
    watto_cobra
  • Reply 4 of 12
    rob53 said:
    What about formatting external RAID HDD as APFS? OWC’s SoftRaid is waiting for Big Sur to make this happen. My RAID can’t be used to backup my Catalina APFS volumes. 
    You do not need to format your NAS as APFS.  But you need to setup something to act like an Apple Time Capsule. For example, my ZFS NAS has a tiny virtual machine running Linux that simulates the Apple Time Capsule.  When I create a backup using the Apple Time Capsule it creates a DMG sparse image for each Mac.  When doing so from a Big Sur Beta test Mac it creates the DMG sparse disk using AFPS.  If I encrypt that image it still works.  This is how off-the-shelf NAS providers like Synology work. They run the open source tools to simulate a Time Capsule over SMB (Netatalk). 

    You can do this without a Time Capsule emulation but it's a bit harder and requires you enable Time Machine over SMB on each Mac which is officially unsupported.  It does in fact work.  Here is the override.  But I don't recommend this method.

    defaults write com.apple.systempreferences TMShowUnsupportedNetworkVolumes 1

    The supported method is if you were to run say a Mac mini with macOS High Sierra or above you could do it that way.  Just mount the NAS storage on the Mac mini  and turn on File Sharing select the mounted NAS folder and right-click it select Advanced Options and check the box to enable Time Machine network location.  It will provide the intermediate Time Capsule like functionality and it will be fully supported by Apple.  You don't even need macOS Server.  It's quite a bit overkill in overhead and cost considering you can do the same with even an old Raspberry Pi and Netatalk open source project for far less and with far less overhead. Heck you could run quite a bit more on a Raspberry Pi 3+ and not even stress it much.  Like a print server and a Pi-Hole (network wide ad-blocker), etc.  But you could probably find alternative uses for the Mac mini to do many more things as well.

    Remember that Mac's are still UNIX and they play extremely well with UNIX/Linux and when there is a will there is a way.  You don't need to do everything with Apple. But Apple still makes things rather easy, you just need to know how to peel back the layers to find it at times.  Bet most people didn't know that macOS High Sierra can run a Time Machine server.   I just checked it's still an option.  
    dewmeMacProwatto_cobra
  • Reply 5 of 12

    neilm said:
    So unless Apple has re-engineered Time Machine, they presumably must have updated APFS to support hard links. Anyone know?
    It appears to be using APFS snapshots instead.  At least on an APFS time machine drive.  Apple only keeps local snapshots for 24 hours so if you wait too long between backups it will likely not have the associated snapshot to delta copy to the Time Machine.  But with APFS and snapshots and the improvements made to Time Machine it is still faster on APFS even if it needs to recopy a large 10GB modified file and overwrite the backup instead of only copying a delta of the two snapshots. If they allow more than 24 hours of snapshots it will consume considerable disk space and even on Linux / FreeBSD systems using ZFS knowledgeable users complain about their disk space disappearing.  Despite those folks should be smart enough to manually manage their snapshots or automate it better with cron jobs.  So I can understand why Apple would place such a snapshot limit to avoid user confusion.  They do things like that all the time instead of providing in-depth technical views and attempt to make it easy; they just arbitrarily set a default configuration and leave it at that.
    dewme
  • Reply 6 of 12
    rob53rob53 Posts: 3,241member
    I’m not using Time Machine. I know this article is about that. I use Superduper to get a clone, that’s not working when going to a RAID (not a NAS) to back up my APFS boot disk. They should have similar issues and fixes. 
  • Reply 7 of 12
    polymniapolymnia Posts: 1,080member
    rob53 said:
    What about formatting external RAID HDD as APFS? OWC’s SoftRaid is waiting for Big Sur to make this happen. My RAID can’t be used to backup my Catalina APFS volumes. 
    I’m running a Promise Pegasus RAID formatted APFS. It works perfectly. Performance is excellent. I was concerned since the marketing around APFS seemed to indicate the tech was designed with SSDs in mind. I guess a fast RAID array performs well enough. 
    watto_cobra
  • Reply 8 of 12
    I just wish Apple would bring back Airport and TimeCapsule. I have yet to find any device that supports TimeMachine which has all of the features those devices offered with the same level of reliability.
    spherictokyojimudysamoriawatto_cobra
  • Reply 9 of 12
    rob53rob53 Posts: 3,241member
    polymnia said:
    rob53 said:
    What about formatting external RAID HDD as APFS? OWC’s SoftRaid is waiting for Big Sur to make this happen. My RAID can’t be used to backup my Catalina APFS volumes. 
    I’m running a Promise Pegasus RAID formatted APFS. It works perfectly. Performance is excellent. I was concerned since the marketing around APFS seemed to indicate the tech was designed with SSDs in mind. I guess a fast RAID array performs well enough. 
    Hardware RAID? Are you using HDDs or SSDs? OWC's RAIDs are software controlled by SoftRAID, makes a huge difference. Supposedly RAID 4 for SSDs can handle APFS.
  • Reply 10 of 12
    maltzmaltz Posts: 453member

    neilm said:
    So unless Apple has re-engineered Time Machine, they presumably must have updated APFS to support hard links. Anyone know?
    It appears to be using APFS snapshots instead.  At least on an APFS time machine drive.
    Do you have a source for that?  I'd love more detail.  I've replicated Time Machine-like backups on my ZFS pool using local snapshots and offsite replication.  But ZFS has been light years ahead of APFS in those areas (and others) which is a huge shame, because my homegrown ZFS solution is FAR faster (in browsing historical snapshots and off-device replication) and far more space efficient than Time Machine.

    Surely this would be bigger news, though, if Time Machine has remotely approached ZFS efficiency.
  • Reply 11 of 12
    maltz said:

    neilm said:
    So unless Apple has re-engineered Time Machine, they presumably must have updated APFS to support hard links. Anyone know?
    It appears to be using APFS snapshots instead.  At least on an APFS time machine drive.
    Do you have a source for that?  I'd love more detail.  I've replicated Time Machine-like backups on my ZFS pool using local snapshots and offsite replication.  But ZFS has been light years ahead of APFS in those areas (and others) which is a huge shame, because my homegrown ZFS solution is FAR faster (in browsing historical snapshots and off-device replication) and far more space efficient than Time Machine.

    Surely this would be bigger news, though, if Time Machine has remotely approached ZFS efficiency.
    https://eclecticlight.co/2020/06/29/apfs-changes-in-big-sur-how-time-machine-backs-up-to-apfs-and-more/

    "APFS doesn’t support directory hard links, so can’t use the same mechanism when storing Time Machine backups. Instead, what appears to function as a form of virtual file system is created using new features in APFS. The volume assigned the role of Backup appears to be a regular APFS volume, and is protected from normal access, even by root. File data is kept as usual in the container’s Physical Store, to which file data is copied during each backup. Apple hasn’t indicated whether this continues to be whole files, or whether only changed data are copied."
    maltz
  • Reply 12 of 12
    maltzmaltz Posts: 453member
    Thanks.  Sounds like they're still trying to do it via hard links instead of at the block level like ZFS.  Shame.  If they were going to do it right, this switch to APFS on the backup volume would have been the time.  It's tragic they weren't able to get an agreement to license ZFS (or OpenZFS) and ended up re-inventing the wheel.  Well, a quarter of a wheel anyway...  lol
    CheeseFreeze
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