Author Topic: OWC article on APFS - High Sierra converts some drives without asking!  (Read 390 times)


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Dear WeatherCat sys-admins,

Other World Computing ( has an interesting article about Apple's new file system: APFS.

It describes an Apple support document that you can read here:

The second paragraph of that Apple support document is a bit of a shocker and I quote with my added emphasis:

When you install macOS High Sierra on the Mac volume of a solid-state drive (SSD) or other all-flash storage device, that volume is automatically converted to APFS. Fusion Drives, traditional hard disk drives (HDDs), and non-Mac volumes aren't converted. You can't opt out of the transition to APFS.

So installing High Sierra will automatically change your file system in some cases and that greatly increases the risk of troubles with the upgrade.  Anyone who is thinking about upgrading to High Sierra better make sure that their existing file system is in good shape before doing so.  I recently upgraded to Sierra but before doing this I checked my file system and discovered some corruption that only Tech Tool Pro was able to repair.

When I do a system upgrade, I prefer to reformat the hard drive, install the new version of macOS and then restore my computer from my Time Machine backup.  This might be a particularly desirable strategy when it comes to High Sierra.  I would also recommend that nobody upgrade until Stu has given the "all-clear".  Judging from the news reports thus far, Apple has been even more sloppy in this bunch of new products than in the past.  Caveat emptor has never been more appropriate.

Cheers, Edouard


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Re: OWC article on APFS - High Sierra converts some drives without asking!
« Reply #1 on: September 25, 2017, 06:23:58 AM »
Regardless of which of the evils one chooses,  be sure that you back up regularly,  those files that you cannot reproduce or it would be a pain in the tush to do.  Do it to an external source.   I have the G-technology drives, one is a 4TB and the other 6TB  Thunderbolt 3.   Now the 6 is solely for my Time Machine and a few choice other things, the 4 is what everything backs up to.

I also have an off site backup on everything,  CrashPlan.  I assume there are others and I am not locked into this one, so like the Red-Green "Man's prayer,"  I can change.

However, back up your files right away, incase you decide to stay with OS Sierra or other, or go with the new one. If you have to reformat your drive, well you don't want to lose your data. Apps/ Programs can be reloaded, but the data , well you get the direction I am going.

I have a fusion drive and yes, I am going to wait until the thundering herd of others make the upgrade.   I would rather wait, but I know me, for the AFS for fusion down the road.
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