Stuck on Getting new Disk Info

Sorry spoke too soon! Resolved after rebooting!

Out of interest, what was the resolution in the end? Just a reboot and trying again?

Hamish

Hi Hamish, yes, the GUI properly loaded after I rebooted. My drive also wasn't showing up until after 5 minutes or so - I'm assuming that it needed more time to load since it is a somewhat larger capacity (4TB)? Thanks for checking in!

Yeah, could be that. It could also be that macOS was retrying and retrying to read some data from it and it took that long for it to give up, I guess.

Good to know, might be worth putting that as an FAQ in my user guide :)

Hi Hamish,

I've finally started the process after receiving a new drive to copy/rescue the data onto, and have a few questions:

1. My new drive is formatted to exFAT, but my old damaged drive was formatted for Mac-only - does this mean that my new drive will also inherit the old drive's filesystem after rescuing? Or will it retain the exFAT format? (I have the overwrite output file/disk option checked.)

2. I'm running ddrescue with the backwards option and have recovered ~1TB data (according to the recovered data number) so far, but is this recovered data simply empty blocks from the back of the disc since the drive originally was maybe at ~25% capacity? Or is the 'recovered data' number representative of actual written/occupied data from the drive?

2. (cont.) If the 'recovered data' number is counting empty data, then would it be more productive to run the process from the start instead? I resorted to backwards because there were some read errors halting the progress in the beginning.

Hi again,

1. It depends on whether you're recovering to a file on the destination drive, or the drive itself (something like /dev/disk3 or /dev/disk3s1)

2. This can not really be known - filesystems tend to spread data across the disk rather than using eg only the first x% that is needed. The safest thing to do is just to try to read the whole surface of the disk.

3. Doing the undamaged parts of the disk first is a good idea - just leave it as it is would be my advice. Depending on how its damaged, it may get progressively worse/slower after trying to read the damaged parts. Also worth noting is that keeping the drive cool with a fan/some kind of active airflow is good. You ideally want it warm to the touch, but not hot - HDDs don't like heat, but do sometimes get hot when encountering read errors repeatedly.

Hi Hamish,

thanks for the quick response!

1. I see, looks like I am writing onto the new drive itself then - in that case I'm assuming the old drive's filesystem will be copied as well.

2./3. OK good to know, currently it's slowed down to about 320kB/s from 16mb/s with around 1.1TB left to go. But no signs of overheating. I think it's finally reached some actual data (hopefully).

Hi,

You're welcome :)

1) Yes, the filesystem will be copied as well in this case.

2) Hopefully it will speed up again, but as long as it's staying cool it should be okay hopefully. It's probably read at least a bit of data, but it's just hard to know, and safer to wait until it's tried to read everything at least once. If you used a mapfile, you can try multiple times with slightly different settings to see if you can scrape more data off it.