Data Loss from Big Sur???

[pmasters]

Upgraded to Big Sur last year and everything went smoothly. But all of a sudden, one of my newest 8TB hard drives doesn't come up anymore. Tried running First Aid from Disk Utility and tells me operation was successful but drive still does not mount. Reading through details, I see errors, so not sure how the operation was successful. Can anyone help me understand what to do so I don't lose the data on this drive?

Running First Aid on “” (disk7s2)

Repairing storage system
Performing fsck_apfs -y -x /dev/disk7s2
Checking the container superblock.
Checking the space manager.
error: (oid 0x7033) cib: invalid o_cksum (0x6dce856d929c1a24)
error: failed to read spaceman cib 8 at address 0x7033
Space manager is invalid.
The volume /dev/disk7s2 could not be verified completely.
Storage system check exit code is 0.

Operation successful.


I've searched Google but the only thing I saw was installing a previous MacOS to try to recover. I am at my wits end.

Thanks.

 

[rpmurray]

Hope you have a backup of the 8TB. If the HD was a spinning disk and formatted as APFS then you might be out of luck getting this fixed. As of now there are no third party disk utilities that can repair an APFS disk. Hopefully, sooner rather than later, a version of DiskWarrior will become available that will work on APFS formatted disks. You could try taking it to an Apple Store but my guess is that all they'd be able to do is erase it and reformat.

 

[fisherking]

can you get to a mac with a previous OS? and see if it mounts there? just a thought...

 

[Unsupported]

Upgraded to Big Sur last year and everything went smoothly. But all of a sudden, one of my newest 8TB hard drives doesn't come up anymore. Tried running First Aid from Disk Utility and tells me operation was successful but drive still does not mount.

I've searched Google but the only thing I saw was installing a previous MacOS to try to recover. I am at my wits end.

Thanks.

Have you tried booting into Recovery Mode and selecting Disk Utility from there?

If you can't start up from macOS Recovery - Apple Support

Learn what to do if you can't get your Mac to start up from macOS Recovery.

support.apple.com

Strange that Disk Utilty see your external drive but it won't mount 🤔

How to repair a Mac disk with Disk Utility – Apple Support (UK)

Use the First Aid feature of Disk Utility to find and repair disk errors.

support.apple.com

... another thought; do you have "External disks" checked here?