External disk no longer showing

[Wando64]

After Apple suddenly forced the Sonoma upgrade on me (and many others, see thread: https://forums.macrumors.com/threads/ventura-magically-updated-to-sonoma.2416284/post-32868611), now my Mac cannot unlock two encrypted volumes on the same external disk.

I suppose the disk could have failed at the same time as I did the upgrade, but this seems so unlikely that I am not going to consider it as an option.
More likely, the upgrade caused some sort of corruption, but I am unable to run First Aid on a volume that cannot be unlocked.

As this was the TM disk for two of my Macs, what other options do I have, that do not involve nuking the disk?

Thanks

EDIT: Never mind. I’ve nuked the disk and restarted from scratch.

 

[okkibs]

There is a major APFS bug that can destroy external encrypted APFS disks. The encryption key gets wiped for some reason making unlocking impossible. I recommend to either use AFPS without encryption or use the external drive encrypted with HFS+. The internal boot SSD is not affected by this.

 

[Wando64]

There is a major APFS bug that can destroy external encrypted APFS disks. The encryption key gets wiped for some reason making unlocking impossible. I recommend to either use AFPS without encryption or use the external drive encrypted with HFS+. The internal boot SSD is not affected by this.

I don’t think I can run Time Machine on HFS+.

Do you have more details about this bug? Any article or thread I could read?

Thanks

 

[Wando64]

By the way, I have numerous encrypted APFS external disks connected to my Mac and this is the only one that has failed, ever.

The only thing that is different about this disk is that it had multiple volumes within the same container.
I have now reformatted it with more traditional partitioning whereby each volume sits within its own container.