LaCie 4TB HD - 2TB - APFS partition lost - Drive Capacity now 2TB

Hi all,

I formatted that ext. HD as follows: 2TB timemachine backup HFS+ and 2TB archive APFS.

The disk fell from a table and the usb C connector died. I opened the case and attached a USB 2.0 connector. The Timemachine partition worked while the AFPS partition did not show up in DiskUtility (devices view). I used the Timemachine partition and now came across the DMDE recovery tool which scanned the drive, found the APFS partition (labeled 'data') and was able to list all folders and files on there. I recovered the files I really needed and then erased the disk in DiskUtility (complete, including the Timemachine partition) to get back my 4TB. However, the disk only shows 2.2 TB capacity in DiskUtility (or connected to a windows machine for that matter). I have hooked it up on the Windows machine now and the seatools from seagate are currently running a 'FixAllLong' sequence which will take another 2 days at the current rate.

I don't understand how the recovery tool can list all data in the 'lost' APFS Container but I am not able to wipe the disk and get the capacity back. What am I missing? Can I not reset the disk into a state where no partitions exist and the whole thing can be initialized once again? Running

 sudo fsck_apfs -n -l /dev/rdisk3

tells me there is no APFS Container present ...

Thank you for any pointers or help on this.

MacBook Pro 15″, macOS 10.15

Posted on Aug 30, 2020 9:38 AM

Top-ranking reply

roadiereloaded Author

Level 1

25 points

Posted on Aug 31, 2020 11:53 AM

The seatools disk drive test 'FixAllLong' finished today after running for 2 days and the disk passed. The APFS partition was never lost, it was just that the USB 2.0 cable I attached limited the drive capacity to 2.2 TB. Since the drive was split into 2 partitions DiskUtil only showed the first partition which happened to be the HFS+ timemachine backup partition.

Unaware of the USB 2.0 connector limitation regarding disk size I assumed that the problem was with the APFS Container which was wrong, much like neuroanatomist assumed that since the disk fell from a table resulting in the original USB 3 C connector board failing that the disk was broken and I should throw it away.

After some initial back and forth about traditions and protocol with my 2 fellow board members here, it was Grant Bennet-Alder who knew that such a USB 2.0 limitation exists and that the limit was usually 2.2TB which is exactly what DiskUtil was showing me.

Since the disk is in flawless conditions, which I have proof for, I will get a new USB 3 connector case and plonk the cest la vie LaCie 4TB thingy into that. No doubt it will serve me faithfully for many years to come.

Allow me to list the following links for anyone else needing to examine an external HD that fell off the table:

good old DOS diskpart - preparing a drive for initialisation:

https://www.seagate.com/de/de/support/kb/how-to-diskpart-eraseclean-a-drive-through-the-command-prompt-005929en/

a solid free disk recovery tool that can read APFS partitions:

https://dmde.com

the venerable seatools for seagate harddisks which are used in LaCie things.

https://www.seagate.com/de/de/support/downloads/seatools/

It was fun and I can't wait to run into another problem we can solve together.

cheers and thank you.

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LaCie 4TB HD - 2TB - APFS partition lost - Drive Capacity now 2TB

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