Erase then restore hard drive from clone

Tech Support
1

My MBP mid-2017 with 1TB SSD (APFS) throws off an issue in Disk Utility (run from the Recovery partition) that “Snapshot Metadata Tree is Invalid”. Essentially the result is that 140GB of the drive is not accessible. The machine boots fine, and doesn’t throw off any errors related to this, as far as I can see. I used tmutil to delete the “dataless” snapshots on the boot drive, as recommended by Apple, but that didn’t resolve the issue. I have no idea what the root cause of the error is. Time Machine backups are working normally. There have been no kernal panics or shut downs. The only significant change was an upgrade to 10.13.6 a week or so ago.

It seems the way out is to do nothing and wait for the worst, or to reimage the boot drive. I am going to reimage. To reimage, I plan to boot into Recovery, erase Macintosh HD then restore from a clone. The clone is on an external SSD (HFS). The clone did not inherit the snapshot issues and checks out fine in Disk Utility.

Make sense?

2

Makes sense to me.:dagger:

Did you need the other 140GB, or were you just poking around to see where it went?

:dagger: No warranties, expressed or implied. Your actual mileage may vary. If you experience headache, nausea, or loss of consciousness, contact your doctor.

3

No I don’t need it now, but I will eventually. (Lots of images.) I just don’t like (a) a hole in the drive and (b) the likelihood that the hole is a symptom of something worse that will fail.

4

It does make sense. If you can I’d make a second clone during the process so your data isn’t in one fewer places for a short time.

1 Like
5

What is the purpose of these “local snapshots”, and why are they not being cleaned up?

6

About Time Machine local snapshots.

7

Well then, there you have it!

Sounds good if it works, which, apparently, it doesn’t always.

Thanks @anon41602260.