Resetting the NVRAM changes Boot Order in BIOS

[jpz4085]

I have 3 separate SSDs running Mac, Ubuntu and Windows. When I reset NVRAM, the boot order changes and the system starts booting directly from the Windows bootloader. So, everytime I do a NVRAM reset and the system restarts, I have to enter BIOS and make the Mac EFI Partition (containing Opencore 0.7.2) as my primary boot disk.

Are you able to boot Ubuntu and Windows through OpenCore? If so try the advice of @Ben42 regarding LauncherOption and I'd suggest you enable RequestBootVarRouting under the UEFI quirks section in your config.plist. The combination of those two features will prevent other operating systems from changing the BIOS boot order. If using this method make sure the OpenCore default boot file (EFI\BOOT\BOOTX64.EFI) is present on the Mac EFI partition then reset NVRAM and boot from the Mac SSD. If it's the first of the three OS disks I believe it should be chosen automatically. The OpenCore entry will be created automatically and the BIOS boot order should not change subsequently. Remember that the OpenCore boot order is managed by its own NVRAM variables and will need reset with Startup Disk after another NVRAM reset but BIOS should be unaffected. This is entirely contingent on using OpenCore as the boot manager for all three operating systems otherwise you will have to continue with your current configuration.

 

[deeveedee]

For what it's worth, I don't have Windows installed anywhere on my rig. When I reset NVRAM via the OpenCore boot menu option, my boot order always returns to a default mode where USB booting is last. Since I prefer to have USB booting first, I must enter BIOS and manually rearrange the boot order.

 

[bugsb]

Clover NVRAM reset via F11 preserves the BIOS boot menu entries, but it doesn't clear NVRAM completely, leaving remnants in NVRAM which are known to interfere with OpenCore, see here.

I'd also like to know a EFI BIOS boot menu friendly (= maintaining) variant of NVRAM reset, in between Clover's and OC's implementation.