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

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.

@neuroanatomist As I have written - the Timemachine partition is working and has been for the last 7 months since the drive fell. Also as I have written the APFS partition gets correctly listed in a third party file recovery program and all files and folders with their real name too and I was able to retrieve those files.

@Grant Bennet-Alder As I wrote - I also of course listed and erased the drive by its immutable device name which is disk3s1 to 3 (EFI, TMbackup and APFS Container). The part that did not function is the connector board - USB C. As I wrote the drive is perfectly accessible with an old USB 2.0 connector board attached. I think that the drive itself is not damaged but that the APFS Container is inaccessible to any partition program resulting in the Drive Capacity being listed as 2TB (which is the size of the up to now functioning partition the timemachine backup used). The missing 2TB were in the APFS Container. Like I said - the seatools program from Seagate (the manufacturer of the drive) lists the drive capacity correctly as 4TB...

I think it is worth trying to low level format the disk if there is a way to do that - which is my question here. :)

as I stated the USB C connector board is damaged as in 'dead'. the drive itself may be fine, and if the issue is the USB 2.0 connector board limiting the size as Grant Bennet-Alder mentioned, then all is good. It was not easy to get information here but you, dear neuroantomist, provided some entertainment and brought a few smiles to my face. Thank you for that.

neuroanatomist wrote:

Disk Utility is a disk management tool, it manages disks, partitions, and volumes – it is not a data management tool. DMDE is, "Disk Editor and Data Recovery Software." If ** cannot see the partition, the logical explanation is that the disk is damaged. Given that you did actually damage the drive, the logical explanation becomes even more likely. It's great that a data recovery tool enabled you to pull the data off the damaged drive. But the drive is damaged, as you state. So, what's your goal here? It seems what you want to do is find a way to do a low-level format of the drive, presumably so you can keep using it.

It's like a mechanic telling you that after you wrecked your car, it cannot be driven safely so you're going to run around town to all the mechanics until you find one that says, "Oh, well see dude, if I just tighten this little wing nut here, your car will be perfectly safe to drive." So you'll tighten that wing nut and keep on driving. Good luck with that.

If you had actually read my original post you would know that I stated that the USB C connector board to the drive is damaged. You may not know this but that is a sata plug in adapter in the LaCie drives, it is not part of the disk...

thank you for the Good Luck wishes, it helped and take a look at this screenshot to see the really immutable device name for a seagate drive in a LaCie casing ;)

that view - by devices is the only view I use. I wrote in the first post that I used the (devices) view and that I erased the complete disk (obviously in the devices view).

And here I get one dude telling me I need to use the devices view, and the other telling me they would not trust a harddrive that fell from a table. I got it. thank you.

Would you 2 like another round of helpful answers badges or can you move on now and we will see if someone else comes along in the next 12 months who knows how to fix this if it can be fixed.

there is no enclosure at the moment. the drive is out in the open. it is connected to an old USB 2.0 connector board and the file recovery tool DMDE listed the APFS container partition called 'data' (the one that is lost and has 2TB) - it also listed all the folders and files in that partition and I recovered the files I needed with it.

In my book, DiskUtil failed to see that partition or how do you explain that this third party tool read all the data from this partition and let me recover any file I wanted?

The seagate tool from seagate which is the manufacturer of the drive lists the capacity at 4TB and DiskUtil lists the capacity at 2TB. In the list by device view.

I have the same view as you and it lists the physical disk, yes and the identifier is disk3, yes and the partitions/child nodes or whatever you want to call them are disk3s1, disk3s2 and disk3s3, yes. I understand what you mean by immutable name, yes LaCie, physical disk, yes. The drive is not perfectly functional at the moment, yes. The APFS partition is lost, remember? but it does seem that the data on that partition was readable and I want to try and see if I can do a low level format of the disk where no partition info remains. If you know of a way to do that it would be helpful. I think you are right not to trust any data to a harddisk that is damaged, yes. But that really goes without saying and is not the issue here.

I am just stumped that DiskUtility cannot see that partition at all and some other program says - "oh, here is that partition and the 12.000 files in their 355 folders that are on it too, which one would you like to save?" Maybe you have an explanation for that so I can move on?