Can't drop and re-create fusion drive on iMac 27" with Catalina

[tonyd5915]

After upgrading to Catalina 10.15.3, the Mac wouldn't boot. It would get stuck on com.apple.PerfPowerServices. So, since I have a (month-old) backup, I decided to try and restore it - but it wouldn't restore. So, I booted into recovery mode, and was going to reformat the hard drive, and then just re-install Catalina. I have tried to re-install Catalina via a thumb drive, booting to an external hard drive, and via the Internet restore process. Nothing works as the error is usually complaining that I don't have permission to do anything to the fusion drive, as it is either "in use" or "read-only". I have been trying to fix this for a week.

So - now I am trying to just delete and re-create the container so I can re-install Catalina. Here is the screenshot from "diskutil list", and a screenshot of the container creation just hanging at 60%. I would think it shouldn't take more than a few minutes to delete the container. Any help is greatly appreciated.

 

[Weaselboy]

First command-option-r boot to Internet recovery (you should see a spinning grey globe first).

The in Terminal run this command to kill the Fusion drive.

diskutil apfs deletecontainer disk3

Then run this command to rebuild the Fusion drive.

diskutil resetFusion

Then quit Terminal and reinstall the OS.

 

[tonyd5915]

I appreciate the reply. I tried booting into recovery mode, but it will only let me try "Internet Recovery", and I get an error message (either "apple.com/support -2002F" or apple.com/support -1005F). When I boot off an external USB hard drive with Catalina installed, and then try "diskutil apfs deletecontainer disk2" (the device name changes when I boot externally), it gets stuck at 60%. I have left it for several hours - and it never gets past 60%. And it fails when I try to do a "diskutil resetFusion".

 

[Weaselboy]

(either "apple.com/support -2002F" or apple.com/support -1005F)

That error message often means you are on a wifi encryption method not supported by Internet recovery. Can you open up the wifi (no password) and try again.

I still should work off the external USB drive though, so this has me worried.

 

[tonyd5915]

It appears you were correct about the wifi having problems. I connected it to the router with an Ethernet cable, and I tried Internet recovery again. This time, I was able to delete the container and reset the fusion drive. The wifi problem is strange, because I could boot off an external USB drive, go to a web page - but I couldn't do anything to the internal hard drive. I couldn't modify it when not attempting an Internet recovery, but just booting off a USB stick to reinstall the OS. It appears to be working now - and I am installing Catalina.

I really appreciate your insight on the wifi problem - you are a genius.