Opencore not allowing 2 OSX Installations where Clover would (Separate Drives)

[Fillwox]

Hey all!

On my last build (GA-Z97-D3H) I had two instances of OSX installed, one as my working copy and one as my test bench so I could install updates etc and make sure it all worked. These were on two physical separate drives. This was achieved with Clover and it was all fine.

I'm on my new build, I've just gotten round to reinstalling it as I had a bad update. Got me thinking I should stick another drive in and have a test boot drive. I stuck a 500GB HDD in along side my SSD which had my previous broken installation on. I installed these from a USB installer with Opencore.

- I installed Big Sur (though this also happened with Catalina also) onto my Test Drive. It all worked fine.
- I installed Sig Sur onto my main SSD successfully but didn't reach setup screen - This is where the issues started

When I had the test drive connected I could boot it fine. However I was using the leftover OC EFI from my old installation on the SSD. I then wiped and installed OSX onto the SSD from the same USB installer. I had to boot from the installation USB as the Opencore EFI was wiped from the SSD when I installed OSX onto it. After the installer had run through for the SSD I could boot to the test drive fine, however when I try to boot the completed SSD installation it gets as far as running through the loading bar, then sits on a black screen indefinitely.

Now I have a feeling this is to do with the order I installed them in and the EFIs, however I also don't understand why this wouldn't be working. When I disconnect the Test drive I can boot to the SSD installation fine using the installation USB, but when I reconnect the test drive I can boot to it but not the SSD. I also can't seem to get OC working on the SSD, if I copy the USB EFI into the SSD EFI it doesn't show up as a bootable entry...

TL;DR - I have two issues -
- 1. My new installation doesn't show on my boot menu, even after copying the installation EFI
- 2. I can't have two installations of OSX for some reason, one breaks the other upon boot

Any ideas? I love how well OpenCore works, but I'm definitely less clued up on it...

Cheers!

 

[dfritchie]

I'm running Big Sur on my NVMe drive/OC efi, and Big Sur Beta on a 2" sata SSD/no efi. I can boot to either one of them from the OC picker. If you are trying to use more than one efi, you have to select the boot disk from your bias, not the OC picker menu just like if you need to boot from a usb stick.

 

[Fillwox]

I'm running Big Sur on my NVMe drive/OC efi, and Big Sur Beta on a 2" sata SSD/no efi. I can boot to either one of them from the OC picker. If you are trying to use more than one efi, you have to select the boot disk from your bias, not the OC picker menu just like if you need to boot from a usb stick

Yeah. I can see both drives in BIOS, however when I try to boot to the SSD OC it loops back to BIOS, but I can boot to the test drives OC. They both have EFI partitions and both have the same OC installations on...

 

[dfritchie]

I'm just saying I only have ONE efi on ONE disk, for both Big Sur disks. I do not use more than one OC EFI. I also have a Windows 10 SSD with its own EFI, I only ever select it in the bios to boot, never through OC even though it is listed in OC's menu. Can't see any good reason to run Windows on an emulated Mac on PC hardware. In my experience trying to use different copies of OC can mess up your NVRam variables and screw up your booting.