Cannot erase a volume in recovery mode

[TassosP]

I erased a Fusion Drive in an old iMac from Recover mode (lost passwords) and was then installing from a TimeMachine backup, starting from Recovery Mode.

After copying over about 130Gb, for some reason the iMac shutdown.

I tried restarting, but it shuts down midway during boot.

Then I went then back to Recovery Mode, to try again the install. It starts, but then tried to Erase the drive before start and hangs.

I then tried Erasing the disk directly form DiskUtility ...

However, the Disk Utility is just hanging for >30 mins without any progress on erasing the drive so I can restart.

So, I am totally stuck now ... any hints on what I can do?

 

[Fishrrman]

Boot to INTERNET recovery (NOT "the recovery partition"):
Command-OPTION-R
at boot.

Open disk utility.
Go to the view menu and choose "Show all devices" (VERY important step).

Now, look at the "list on the left".
The topmost item should be the physical internal drive. This is what you want to erase.

Once it's erased, quit disk utility and open the OS installer, and try again.

When done with the install, begin doing a "new setup".
At the appropriate moment, setup assistant will ask if you wish to migrate from another drive or tm backup.
YES, you want to do this.

Connect the tm backup, give setup assistant time to "digest" everything on it.
When done, setup assistant will present a list of stuff to migrate.
I'd leave everything checked and just "let it go".
When done, you should see your old login screen.