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[Solved] Is there any tool yet that repairs APFS containers?


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So it seems that something is wrong with the snapshots on the SSD of my MacBook Pro - migrated to APFS via normal upgrade going from 10.12 to 10.13. It is now on 10.14.2. (I’ve never previously needed to do a clean install.) 

Disk Utility, via Recovery mode, gives me the error below. ie. It can’t fix it. 

I have a suspicion I might need to do a clone, wipe the drive, then clone back?

Both DiskWarrior and TechTool Pro are saying the next major version will support APFS repairs and Drive Genius simply says APFS rebuild not supported.

Also note, macOS on this partition is still running OK and I suspect this background snapshot inconsistency may have existed for a while. The noticeable impact is when I run any “optimisation” that wants to check the container (like Safe Mode) and it takes a loooong time to run. But I’m getting some inconsistencies from tools that analyse how my disk space is used - with about 40GB unaccounted for even after digging deep. 

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OK - so I created/confirmed a Carbon Copy Cloner clone on an external SSD (this Samsung T5 is pretty good!), then used a USB stick with the Mojave installer to fully erase the internal drive, then install 10.14, then created a temporary user to allow a login that could perform the 10.14.2 update, then ran Migration Assistant to pull everything back from the external SSD.

All went pretty well, though I think the existence of the "temporary" user account, which meant my usual account was created with id 502 rather than 501, caused Little Snitch to revert to "factory" rules. 

I have run Disk Utility First Aid and it now completes successfully (as below).

Tip/Discovery: First Aid seems to now allow repairs to be run on the current startup disk but says that it will "freeze" other apps while it is doing it !??!

Great. Did you try to boot from the CCC backup or run disk utility on it? Perhaps the problem was fixed that way, so you could have just made a backup back from such Samsung Portable SSD T5 to the Mac, without using Migration Assistant.


There is not such a tool so far, so no upgrade to High Sierra or Mojave is recommended. This is a deal breaker!


BTW, the fact that Disk Utility reports operation successful with tick on green circle WHEN THE DISK HAS PROBLEMS NOT FIXED is shocking and terrifying. Mostly when you consider that error details only show if you click the expanding arrowhead triangle on left (Show Details). And that even then, you may not notice such error lines, since they are not highlighted in red color or otherwise. NOT GOOD.

Yes, I would assume that the snapshot problem would also have been solved with a clone back to the erased internal drive. However because there seemed to be some unexplained disk usage I used migration assistant to improve the chances of not copying back “orphaned” files. 

I don’t know why a failure to verify a snapshot by Disk Utility isn’t highlighted in red and allows the first aid to complete with a successful message. Wonder if I should report this and see what sort of reply I get?


I suggested not using Migration Assistant because I have had problems with it in the past, not copying some files and --worst of all-- not warning about it (I noticed the issue because the copied size was quite different and smaller than the one of source booting disk) that SuperDuper copied perfectly.

As far as I know, Migration Assistant may generate such issues when there is some kind of problem with the source disk. It works OK if the disk is fine, but may not work well otherwise, and you may not know. Thus, I use SuperDuper, just in case.

On the other hand, are you using the latest macOS 10.14.2 (18C54) version? Which version of Disk Utility?