Re: Creating an (Apple) EFI bootable media

[Bean]

On Thu, Oct 1, 2009 at 11:17 PM, Michal Suchanek <address@hidden> wrote:
> Hello
>
> Is there a way to reproducibly create Grub bootable media (CD, USB
> stick) that can be used with Apple efi?
>
> I tried some ways of blessing the boot loader which I found on the net
> but none works.

Hi,

You should format it as GPT, MBR may not work. The fs of choice is
hfsplus, although I heard someone have successful boot with FAT.

To bless the disk, use something like this: (only available for hfsplus)

sudo bless --folder=/Volumes/USBDISK --file=/Volumes/USBDISK/efi/grub/grub.efi

bless writes the location of boot file to the hfsplus header. bless
doesn't work on FAT.

At startup, you need to press the Option key to show startup disk, and
select the usb disk.

The following command writes the boot device to nvram so that it's
used by default:

sudo bless --folder=/Volumes/USBDISK
--file=/Volumes/USBDISK/efi/grub/grub.efi --setBoot

>
> Also the default core image probably lacks some essential parts. I
> managed to load it as rEFIt shell command by placing it in the tools
> directory but it complained about "prefix" not being defined and I
> seemingly had no commands - the help command was not available, and
> pressing tab did not show anything.

You can add the command to the generated EFI image with grub-mkimage,
here are the list of modules I usually use:

./grub-mkimage -d . -o grub64.efi minicmd part_gpt part_msdos
part_apple fat ext2 hfsplus hfs ntfs reiserfs xfs iso9660 udf ls
search loopback linux chain reboot halt appleldr help configfile
hexdump loadbios memrw fixvideo crc sh video efi_fb gfxterm font png
coreui loadcfg menutest gfxmenu textmenu

>
> For some reason I cannot boot rEFIt from external media either but I
> can bless rEIFt on the built-in HDD.
>
> I don't know what the Apple bless commnad is supposed to do so I have
> no idea if whatever it did was correct.
> I suspect different arguments than those advised on the various web
> pages are needed when blessing a boot loader on an external medium (as
> opposed to the root volume).



-- 
Bean

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