Full notes are here but below are the basics from rohiths answer When you reboot you will get a limited grub terminal. Executing 'grub-install /dev/nvme0n1' failed. The installer will appear to fail as per my question above. It will create a small partition with /boot/efi and take up the rest of the drive with / as you know there is no need for a swap partition as Ubuntu now uses a swap file. From the 20.04 iso on a USB let the installer do it's thing. So, any ideas how I can get the installer to work or how I can manually install a grub?

From that program if I terminal and lsblk it does not even show the nvme0n1 drive. When I boot up with boot-repair the program runs but it does not detect anything. I have tried several manual grub-install options from these pages but the most common error then is /cow is busy and it cannot be unmounted. I have reformatted the entire drive as gpt using gparted and basically started from scratch but cannot find any partition combination that will let the installer complete (other than forcing it to install when there is no EFI partition in which case the installer does NOT fail but obviously the Mac mini fails to boot to anything). I have tried several of the Matt Gadient (legend) bootable iso versions. I am unable to follow this good advice Install ubuntu 18.04 on mac mini 2018 as I cannot install rEFInd in that manner. No matter what I do the install fails and the Mac mini subsequently boots into an old Grub 2.04 with limited capabilities. My flash drive has the that has been made into a bootable USB by the startup disk creator on my working Ubuntu 14.04 LTS laptop. So when I turn on the Mac mini and hit the Alt key it shows me the two icons to select boot, the hard drive and the flash drive. I have bypassed the T2 chip by booting into recovery mode and selecting 'No Security' and 'Allow booting from external drive'. My install (dedicated Ubuntu NO dual boot) fails with the famous Įxecuting 'grub-install /dev/nvme0n1' failed.

I have a brand new 2020 Mac mini (Intel i3 quad core chip).

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