Disk Utility First aid - Object map is in valid

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rhymes-123 Author

Level 1

9 points

Disk Utility First aid - Object map is in valid

I have encountered some problems today, I had to restore from a Time Machine backup but

the issues don't seem to have been gone away.

I have tried to run Disk Utility and this is the result:

Verifying file system.

Volume could not be unmounted.

Using live mode.

Performing fsck_apfs -n -l -x /dev/rdisk1s1

Checking volume.

Checking the container superblock.

Checking the EFI jumpstart record.

Checking the space manager.

Checking the object map.

Checking the APFS volume superblock.

Checking the object map.

error: om: btn: invalid o_oid (0x1616fe)

Object map is invalid.

The volume /dev/rdisk1s1 could not be verified completely.

File system check exit code is 8.

Restoring the original state found as mounted.

Operation successful.

Any ideas? As I said restoring (which formats the disk) from a time machine backup doesn't seem to fix the problem.

MacBook (13-inch), macOS High Sierra (10.13.1)

Posted on Nov 28, 2017 2:52 PM

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Answer 1

Best reply

rhymes-123 Author

Level 1

9 points

Nov 30, 2017 12:10 AM in response to Old Toad

Fortunately it was just a file system corruption.

I did the following:

bootable USB image of High Sierra
clean install from that
restore from time machine backup with Migration Assistant

everything now works perfectly and disk utility says the disk it's ok :-)

Thanks!

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Answer 2

rhymes-123 Author

Level 1

9 points

Nov 28, 2017 11:56 PM in response to Old Toad

Yes I do have a backup, that's how I tried to restore my mac.

Before going to Apple Genius Bar I wanted to exhaust my options because the SSD drive is not the original (my MBP is from 2012) so I don't think Apple will do anything about it. The drive it's a Samsung 850 Pro 512 GB

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Answer 3

rhymes-123 Author

Level 1

9 points

Dec 1, 2017 5:07 PM in response to kylejv1993

@kylejv1993 if you click show details you will find out what happened wrong.

BTW I had another issue with the file system. I am confident that the drive it's okay (I did many smart tests with smartmontools) so I think the issue lies with APFS and my SSD.

Fortunately I think I found a solution by installing OSX High Sierra with HFS+ instead of APFS, the old file system that never gave me any problems in the past.

Here it's how you can do it: http://osxdaily.com/2017/10/17/how-skip-apfs-macos-high-sierra/

I did it like this: boot from High Sierra usb, partition the disk with hfs+ (osx extended journaled), manually installed High Sierra like in the article and then restored from my Time Machine

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