APFS and Time Machine

Saymee

This one sounds weird. Unless your Time Capsule has a SSD installed (unlikely) then it will not work as it has a HDD by default and this cannot be converted to APFS yet. I formatted an external SSD as APFS and as soon as I wanted to use it for a Time Machine backup, I received a message that it cannot be used for a TM backup unless it is reformatted as HFS+.

Your TC's HDD can currently only be used by TM if it is HFS+. I have the same setup and even when I tried, I could not even format the drive. Of course it would be great if APFS could be used with all drive types, but this feature is not yet available.

Contributors please correct me if I have it wrong here.

Hi andrieso! Just to say that as far as I know you are quite correct — Apple´s advice seems to be to leave all drives used by Time Machine in HFS+ format for the moment. But crazily, Disk Utility shows the option to convert my Time Machine drives (WD 2 TB spinning drives) into APFS format, which I won't do, of course! Cheers, Ian.

Other than reformatting the drive with HFS+ there is not much you can do. How High Sierra managed not to see that this is actually a normal HDD and should not be formatted APFS, I cannot quite tell. Nevertheless, if backing up your work is important and your Time Capsule did it in the past, then rather continue. In the same situation I would rather take a chance and lose older backups, reformat with HFS+, and run a full backup again, than rely on an APFS formatted drive that cannot be trusted and will ultimately fail - which was the problem you started with.

As a side note, I always keep two very different backup strategies running: I use my TC for all backups by default, and in case of a disaster I can do a complete recovery from that, recovering not only data, but also the OS and apps running on it. But I also make sure ALL my data is stored offline as well and to ensure this works, I have folders for my data that are not tied to the OS. Photos (the oldest photo I have there dates back to 1954), iTunes Library, Outlook's OLM file, documents and so on are all stored on folders on what I can call a D:\Data drive, sort of like in a Windows environment. One copy command copies the entire folder along with everything in it to an external drive. You can always reinstall a damaged OS and its apps. But losing your actual data is just not on.

No, nothing you can do at the moment as I understand things, as andrieso posted: "Other than reformatting the drive with HFS+ there is not much you can do."

And as Luis Sequeira posted Time Machine can't yet work with a drive in APFS format, and it´s not clear when Apple will get around to sorting this out, if ever, because the future seems to be APFS on SSD drives. I´d reformat your TC back to HFS+ if you want to carry on using it with Time Machine. Hopefully you have other backups! Ian.

Using Disk Utility in Command + R:

To convert internal partition (500GB) of HD to APFS took a few seconds. Cool!

I thought this was awesome. I wrongly assumed my 2TB Time Machine (USB 3) would take just a few minutes. The first third of the progress bar was rather quick, but the second third had taken 6 HOURS. It was crawling, like watching grass grow. I was thinking I could have driven to Best Buy, bought a new drive, format it to APFS and copy Time Machine over to it in far less time. It was doing some sort of pre-inspection report to be sent to Apple. It hadn't even started yet! (Note: the Mac is unusable during this time.)

I couldn't wait. At that rate, it wouldn't finish until after midnight (assuming there isn't a 6+ hour post-install report to be sent, too). This wouldn't be so bad if there was an estimated time below the progress bar warning me. I had tasks to do like important emails, so I Restarted my Mac.

With Time Machine taking so long (longer than any update should, longer than transmitting the entire contents as if on dial-up) and the boot drive being grayed out (later, finding everyone else trying to update to APFS was met with this confusing decision by Apple), APFS has me urging people NOT to try this. Without an APFS on the boot drive, any advantage is completely lost.

(I'm having MS Windows, hours long, reinstall flashbacks from my tech days.)

There is nothing preventing you from converting and using an HD formatted as APFS; they work. It is just that Time Machine still can’t use APFS in the TM backup drive.