Downgrading to Sierra Questions

[itguy61]

I have a Superduper backup to restore from but of course my internal SSD on my iMac is now formatted with APFS. I am reading that just deleting this drive with disk utility leaves the container out there for the APFS drive. Has anyone restored back to Sierra with a backup and how did you handle getting the main internal drive back to the old formatting type?

I apologize as I am sure this has been posted but the search keeps erroring out of me with some type of security error..

Thanks,
Tim

 

[Weaselboy]

Boot from your SD drive then start Disk Util and enable show all devices like in my screenshot. Then select the drive hardware itself at the very top of the left column like in my second screenshot and erase back to HFS+. By selecting the drive up top you are erasing the entire disk, including any APFS containers.

Where you would have a problem is if you just selected Macintosh HD to erase, as that would not get rid of all the other partitions/containers.

 

[Fishrrman]

OP wrote:
"Has anyone restored back to Sierra with a backup and how did you handle getting the main internal drive back to the old formatting type?"

VERY IMPORTANT QUESTION:
Is your SD backup in HFS+ or is it in APFS?
If it's in HFS+, do this:

The best way to do this is with a USB flash drive installer.
1. You'll need a copy of the Low Sierra installer
2. You'll need the free "boot buddy" app. Get it here:
https://sqwarq.com/boot-buddy/
3. You'll need a USB flashdrive 8gb or 16gb
4. Use BB to create a bootable version of the installer on the flash drive. Takes only a few clicks of the mouse.

Now...
a. Boot from the USB flashdrive, but DON'T run the installer, instead quit it for the moment.
b. Open Disk Utility and ERASE your ENTIRE internal drive to Mac OS extended with journaling enabled.
c. Now close Disk Utility and re-open the installer
d. Run the installer to install Low Sierra. It will go through one or more reboots and take some time.

When the install is done, and the setup screen appears, do this:
1. Connect the SD backup
2. At the appropriate moment, setup assistant will ask if you wish to migrate data. YES, you want to do this
3. "Aim" setup assistant at the SD backup. Select what you wish to migrate.
5. Let setup assistant do its thing -- could take some time.

When done, you should be presented with a login screen, and then a desktop representing "where you were" at the moment of your last SuperDuper backup.

Congratulations, you did it "the easy way" !

 

[jbarley]

As Weaselboy suggested, easy-quick-done!
Boot from SD clone, erase target drive, clone SD back to newly erased drive.

 

[itguy61]

Thanks for the info, greatly appreciated!