Would you nuke and reinstall?

[monk64]

I'm running up-to-date macOS Mojave on a late 2015 iMac with the 3TB fusion. Was trying to set it up for Bootcamp (yes, this model supports it), and am seeing errors when it does the disk check:

The volume Macintosh HD was formatted by hfs_convert (945.200.129) and last modified by apfs_kext (945.230.6).
Checking the object map.
Checking the snapshot metadata tree.
Checking the snapshot metadata.
Checking snapshot 1 of 5.
warning: total_segments reached
warning: object (oid 0x4000114977698): Unable to mark physical extent range (0x4000114977698 + 114) allocated for space verification 
error: btn:1: invalid key order (1) oid 462294 / oxid 0
Snapshot is invalid.
The volume /dev/rdisk2s1 could not be verified completely.

Operation successful.

Get the exact same messages when I boot to single user mode (CMD-S) and run fsck_apfs manually there, or when I run disk utility in the CMD-R recovery mode.

I fooled around with some tmutil commands to delete all local snapshots - no difference. Also ran a TM backup to completion - no errors, but also didn't change the above.

CCC also reported a couple errors, though after deleting a file that it was stuck on, CCC ran successfully last night.

I'm wondering if I need to nuke the system and restore from TM?

Seems to me that APFS is not quite baked :-( If I do nuke, can you still use HFS+ on Mojave?

 

[Raz0rEdge]

Are you backing up TM locally or to an external drive? You cannot use HFS+ on Mojave, it only supports APFS for all storage types. If the issue you are seeing is a hardware/drive issue, a re-install might mask it.

 

[monk64]

Are you backing up TM locally or to an external drive? You cannot use HFS+ on Mojave, it only supports APFS for all storage types. If the issue you are seeing is a hardware/drive issue, a re-install might mask it.

I use a Synology NAS for backup. I backup two other Macbook Pros to it without issue (and the backups for this iMac to it work fine as well).

Of course, it could always be a hardware issue but...I just had the drive replaced by Apple less than a month ago, as the previous drive had other, unrelated issues (i.e., it stopped working entirely ;-)