B75M-D3V Ozmosis F12 does not boot, bcfg boot failed

  • You must ensure to add the right entry since APFS Containers work different than the know structures in HFS+
    The APFS driver maps the containers content to fs2 but it's actually not it's physical position since it's only mapped there and will not generate a valid boot entry at all. To generate a valid entry fire up terminal in macOS an type

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    1. diskutil list

    you'll get an output similar to mine:

    as you see there a two drives in the output one physical drive called disk0 in my case and one synthesized drive called disk2 in my case. Disk2 represents the content of disk0s2 since disk0s2 is a container which combines all the stuff listed on disk2 in one single partition. Without the APFS.EFI driver loaded there would be no access to disk2 since it is created by the driver it self. But how to add a valid boot entry?


    We need some information about the main partition inside the Container. In my case the main partition inside the container is called Sierra and resides on disk2s1 and as all partitions in macOS have their own universal unique identifier it's a good idea to look for the UUID of the main partition and write it down. To obtain this information we again use the diskutil command

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    1. diskutil info disk2s1 | grep "Partition UUID"

    will output the UUID of the main Partition (you'll have to replace disk2s1 with your values). In my case the command output read

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    1. iMac:~ giesbertdumpich$ diskutil info disk2s1 | grep "Partition UUID"
    2. Disk / Partition UUID: 3C199D35-CB13-3164-9BF0-22821813CB91


    Now we know everything needed to create a valid UEFI Boot entry so let's reboot into EFI shell and see on which FS our main partition can be found inside the container. Simply browse to all available Filesystems with die fsx: and ls command (replace x with any number). As soon as you find a FS which holds a folder named like the UUID you obtained before change the directory with cd and check wether /System/Library/CoreServices/boot.efi is present or not. If it's present congrats you found the right place if not try the next fs and so on. Once you found the right one add your boot entry,in my case I had success on fs4. I used

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    1. bcfg boot add 4 fs4:\3C199D35-CB13-3164-9BF0-22821813CB91\System\Library\CoreServices\boot.efi "macOS"

    and Bingo the entry appeared and I am now able to boot HighSierra just by selecting this entry in the F12 bootmenu or in the OZ gui.