Recovery Mode > Disk Utility > Backup with External SSD > hanging around 25% > stuck "Shrinking APFS data structure"?

CJMacDaddy wrote:

I am in recovery mode using disk utility & I've plugged in my external SSD to back up my internal. I have twice as much space as I need for the BackUp - but I have other backups on the drive too... I went to add a partition and it has been stuck at the same spot (approx 25% on status bar) & the Details are hung on "Shrinking APFS data structures". went to add a partition and it has been stuck at the same spot for at least 3 or 4 hours... I have other backups on the same external drive that I would prefer not to jeopardize. I have other copies of them too - all different formats on a total of 4 other SSD., but I have had to spend a tremendous amount of time & it's a strenuous learning curve that I would have to re-encounter... I am wondering if this is hanging. and how do you check that it's not frozen?

I am already running the program & can't get to the terminal or the eject icons because the Details Screen is in the foreground and those are in the background which I cannot access...

What are my options? Hold down the power and force it to shut off? or Command+Option+Shift with the power button to turn it off. Will this ruin everything I accomplished and wipe the whole drive? I am hoping there is a "safe" option that can get me past this hurdle.

OR should I sleep on it, and hope that it completes by the morning? with it not compete by morning, would my last and final choice be to hold power down and risk all? is an external SSD and

Volumes share space within in a Container without penalty—

Add, delete, or erase APFS volumes in Disk Utility on Mac

Manipulating Containers and regaining disk space not so much...

to regain all disk space erase/reformat/initialize the drive as new and start over

Erase and reformat a storage device in Disk Utility on Mac - Apple Support

If you are stuck—You can always force quit a shutdown by holding the power button/TouchID for ~6-10 sec.

Force Shut down your Mac.

Log out, sleep, wake, restart or shut down your Mac

Shut down or restart your Mac - Apple Support

If you value your user data

3-2-1 Backup Strategy: three copies of your data, two different methods, and one offsite.

More than one device, more than one backup methodology.

CJMacDaddy wrote:

I am in recovery mode using disk utility & I've plugged in my external SSD to back up my internal. I have twice as much space as I need for the BackUp - but I have other backups on the drive too... I went to add a partition and it has been stuck at the same spot (approx 25% on status bar) & the Details are hung on "Shrinking APFS data structures". went to add a partition and it has been stuck at the same spot for at least 3 or 4 hours... I have other backups on the same external drive that I would prefer not to jeopardize.

Then why are you performing such a risky major undertaking as modifying partitions especially for a drive used for backups? This is making major changes to the drive and the existing file systems. This is another perfect example of why I never recommend having multiple partitions on a drive especially after important data already exists on the drive.

I have other copies of them too - all different formats on a total of 4 other SSD., but I have had to spend a tremendous amount of time & it's a strenuous learning curve that I would have to re-encounter... I am wondering if this is hanging. and how do you check that it's not frozen?

Good! Maybe you should consider a better backup strategy if this is not a simple restore operation.

I am already running the program & can't get to the terminal or the eject icons because the Details Screen is in the foreground and those are in the background which I cannot access...

What are my options? Hold down the power and force it to shut off? or Command+Option+Shift with the power button to turn it off. Will this ruin everything I accomplished and wipe the whole drive? I am hoping there is a "safe" option that can get me past this hurdle.

OR should I sleep on it, and hope that it completes by the morning? with it not compete by morning, would my last and final choice be to hold power down and risk all? is an external SSD and

It is hard to say when to give up hope. It does sound like the system is frozen though. Hopefully none of your open apps are attempting to access the external drive you are trying to resize. Most likely you are going to need to erase the external drive and restore the contents from a backup.

You should always have frequent and regular backups of your computer(s) and all external media (including the cloud) which contains important & unique data (even including unique arrangements of your data).

Time machine is happy to add another drive at any time, and can continue to use multiple drives, alternating backups to each drive, with keeping each drive an independent backup set.

Regardless of the status of this adventure, which may end badly if you intervene, you should find another drive at least as large as what needs to be backed up and begin a new backup set on it.