Why does a NVRAM Reset wipe GRUB from the boot menu?

[agent2]

Hello everybody,

As some of you might know, I’ve got a triple boot system running with macOS 11.4 and Manjaro Linux 21 running in their own 1TB partitions on my NVMe SSD. Windows is own 500GB SATA SSD, but that’s not relevant here.

What I‘m having a hard time solving is the following problem:
When performing an NVRAM reset, like when updating OpenCore, my GRUB bootloader to get into Manjaro gets wiped out. Every. Goddamn. Time.

What shall I do? When selecting my EFI partition of my SSD, it defaults to OpenCore, which is good.
But I always need to follow this tutorial video how to restore GRUB, which is pretty tedious, especially when one hits the reset NVRAM button by accident.

Can someone guide me on how to keep GRUB there permanently? Windows Boot manager seems to always stay there, so why can’t GRUB do that?

Thanks for your help and input in advance!

 

[Shaneee]

I can't give you a definite answer but I'd assume this is a reason I see a lot of people chain-loading rEFInd with their macOS/Linux setups.

 

[Moozuki]

Grub and OC are sharing the same EFI partition. Only one can be in charge. Windows in not an issue here because it's on it's own drive with it's own EFI all to itself.
The solution is to use separate drives, or chain load with rEFInd. Since one is complicated to set up, I just use separate drives for macOS, Windows 10, and Mint Linux. You would be having the same issue if Windows and macOS were on the same drive so it's not just a Grub thing.

 

[agent2]

Grub and OC are sharing the same EFI partition. Only one can be in charge. Windows in not an issue here because it's on it's own drive with it's own EFI all to itself.
The solution is to use separate drives, or chain load with rEFInd. Since one is complicated to set up, I just use separate drives for macOS, Windows 10, and Mint Linux. You would be having the same issue if Windows and macOS were on the same drive so it's not just a Grub thing.

OK I’ll give that a look later on! Thanks for the info!
I’ll report once I’ve got something working!

 

[agent2]

Could someone provide a guide I could follow to install rEFInd? I can’t really find a simple and clearly documented page.

 

[Ezaul]

Good night My dear friend.

Here I also use triple boot Windows 10, Ubuntu , Big Sur

The best thing to do is, as our colleague has already mentioned, is to make each system on your HD, SSD or NVMe... that's what I did here too, I had the same problem as you!

Another solution would be to install OPENCORE EFI on the same partition where the Windows EFI is.

 

[Ezaul]

See my configuration today:

SanDisk SDSSDX120GG25 - 120GB - Linux.
SanDisk SDSSDH3 1T00 - 1TB - Jogos.
Seagate ST6000DM003 - 6TB - Backup.
NVMe XPG GAMMIX S50 - 1TB - Windows 10 Pro.
NVMe Corsair Force MP600 - 1TB - BigSur 11.6 ----->> Select BOOT

I use to boot NVMe Corsair Force MP600 where EFI OPENCORE is installed along with BIG SUR

So I never had a problem with grub, rewrite the EFI it was all independent