MP 1,1-5,1 Booting GRUB-EFI on a cMP

[theMarble]

I want to get a cMP to use as a Linux workstation, and only Linux, I don't need macOS to be on this computer. Can a cMP boot straight to GRUB without using the Option menu or rEFInd? I've only heard GRUB-only ever being used on MBP's and it had issues with backlight, trackpad... but all of that isn't on a cMP so in theory it should work???

 

[startergo]

I want to get a cMP to use as a Linux workstation, and only Linux, I don't need macOS to be on this computer. Can a cMP boot straight to GRUB without using the Option menu or rEFInd? I've only heard GRUB-only ever being used on MBP's and it had issues with backlight, trackpad... but all of that isn't on a cMP so in theory it should work???

Do you really need GRUB? You can always bless an EFI loader in the ESP partition.

OpenCore on the Mac Pro

Use my script and gfxutil to view EFI boot vars and see how bless and Startup Disk effects the boot bars. https://forums.macrumors.com/threads/documentation-on-all-parameters-for-nvram.2239034/post-28518123 bless --mount /Volumes/EFI --setBoot should point the EFI boot vars to the partition...

forums.macrumors.com

bootoption/bootoption: EFI boot menu manipulation for macOS, like efibootmgr (github.com)

 

[theMarble]

Do you really need GRUB? You can always bless an EFI loader in the ESP partition.

OpenCore on the Mac Pro

Use my script and gfxutil to view EFI boot vars and see how bless and Startup Disk effects the boot bars. https://forums.macrumors.com/threads/documentation-on-all-parameters-for-nvram.2239034/post-28518123 bless --mount /Volumes/EFI --setBoot should point the EFI boot vars to the partition...

forums.macrumors.com

bootoption/bootoption: EFI boot menu manipulation for macOS, like efibootmgr (github.com)

So rEFInd then? It will still have to reboot when I select Linux as all of my special configs / dotfiles are made for GRUB and I don't want to re-write them.

Would the boot process be:

- Press Power Button
- Load rEFInd
- Select Linux option
- Auto reboots into GRUB
- Select distro in GRUB meny
- Boot into Linux

 

[startergo]

Auto reboots into GRUB

If you look at @joevt Boot loader he is not booting Grub. Shimx64.efi is a UEFI boot loader.

dumpallbootvars BootOrder: Boot0080 Boot0000 Boot0000: 1, "ubuntu", "HD(1,GPT,19D44A4A-72CE-488C-869C-32776991515D,0x28,0x64000)/\EFI\ubuntu\shimx64.efi" Boot0080: 1, "Mac OS X", "PciRoot(0x0)/Pci(0x1F,0x2)/Sata(0x2,0x0,0x0)/HD(12,GPT,01A40057-B54C-4974-AF84-A70CD2E937FF,0x6FC68A00,0x19088)", "maxmem=63488"

If you use Balenaetcher to create your installer it will do it in EFI mode. If you use RefindPlus you will also have boot screen on a newer metal supporting card. You can set Linux as a default loader option in the RefindPlus config file, so it will automatically boot to Linux every time. You can set a boot pause of few seconds in the RefindPlus config file for those rare occasions you want to boot any other OS installed on the Mac.