I’m tired of googling it I can’t find the definitive answer. Want to know before i waste my time converting the drives to APFS. I’ve already done all the drives but time machine one. So all or nothing no going back now.
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Do Time Machine backups work on external HD with APFS?
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Do you know this for fact? Cuz I’ve read it both ways. Does apple say it anywhere?
I haven't experienced it firsthand, but here is a screenshot (and accompanying article) that shows what happens if you try it.
Well, Time Machine was designed with HFS+ in mind, with all the limitations it carries. However, I can see in the future a Time Machine that takes advantage of all APFS features, such as snapshotting and so on. APFS duplication, snapshots and clones are so damn fast that it'd make Time Machine much, much faster an reliable.
Having said that, there's still no support for APFS on regular hard drives, the most popular use for Time Machine.
Having said that, there's still no support for APFS on regular hard drives, the most popular use for Time Machine.
This is not correct. High Sierra does not automatically convert regular hard drives to APFS but there's nothing preventing you from formatting one as APFS. It works just fine for all things other than being a Time Machine target.
I stand corrected. I could convert an external USB HDD to APFS, but not the boot HD (yet). I'd say support is 50/50 as of now.
Time Machine can read HFS+ or APFS disk drives as the source for a backup. The destination must be HFS+ because Time Machine uses a non-standard piece of magic, directory hard links, which are not supported by APFS.
Time Machine can restore to either file system type since that is standard directory and file operations.
DS
Time Machine can restore to either file system type since that is standard directory and file operations.
DS
Regardless of the answer, you should keep all your back-up drives formatted as HFS until APFS becomes more mature and widespread. APFS is not backwards compatible with prior OS's if you ever wanted to go back to Sierra. In general, HFS is mature and compatible - that means it is perfect for backups. I'm not sure what advantages APFS would bring to a backup drive. You just use it to dump backups and data and don't need the advantages (used loosely) of APFS. You can definitely convert all external drives (SSD, HDD, Thumb) to APFS manually using DU, but I don't see why you would at this point. That said, CCC5 can handle APFS both ways - read, write, restore. CCC5 is my preferred method to safeguard. I also do Time Machine, but have never gone to TM when in a bind. Always restore a recent image and move on.
I converted my External Time Machine to APFS and it stopped working, I had to format the whole drive and backup nearly 2TB of data again, always fun.....
APFS duplication doesn't help time machine. If it did, hard link files would be fine. The reason is, you have a directory hierarchy with millions of files but nothing changed. You still don't want to muck around with millions of duplications, even APFS fast ones. This is why directory hard links are genius. One hard link and bam you are done.