Arch Linux

vee

Member

Registered: 2012-10-30

Posts: 2

gpt btrfs and grub2, grub issue

Hello,
I'm installing the latest Arch, following the btrfs root guide, the GRUB2 GTP guide, and the non+beginners guide and persistently am being stumped with GRUB2; hopefully my description isn't too convoluted/uninterpretable.

I've used gdisk to partition my hdd into 2 segments: a 200 vfat (using both code EF00 and EF02) and btrfs for the rest.
I've mounted sda2 on /N2 and created a sub-folder for boot (/N2/boot) then created a subvolume __active (/N2/__active), and subvolume for home,usr,var (/N2/__active/{home,usr,var})

Mounting it all together works fine in the chroot environment, installed grub-efi-x86_64, build the mkinitcpio-btrfs.
created the directory /N2/boot/efi, then mounted the vfat to it - then created the EFI folder within.

Installed the Arch UEFI app under /N1/EFI/arch_grub (which is /N2/boot/efi/EFI/arch_grub due to the mount/or-bind), and then installed the grub-config under /N2/boot/grub/grub.conf

After all is done, bootup my laptop (Dell Latitude E6320 with A15 bios) and "GRUB _" is displayed, and hangs.
I've toggled the vfat code from EF00 and EF02 (mentioned once before) and now am somewhat lost in the logic as I believe I've covered all the steps, but apparently am missing something.

I've went ahead and wrote all my commands used and pinned them on pastebin; perhaps somebody can point me in the right direction or point out directly where I've made a (or multiple) mistakes?

Thanks in advance

WonderWoofy

Member

From: Los Gatos, CA

Registered: 2012-05-19

Posts: 8,414

Re: gpt btrfs and grub2, grub issue

What you want to be doing is creating a uefi system partition.  That should be fat32 (or fat16), where your boot files will be located.  You actually don't need grub at all, but if that is what you are used to, then so be it.  So you need to do the grub installation like the wiki says, but then you need to create a bootloader entry with efibootmgr.  Your other alternative is to simply place grub on the efi system partition as /EFI/boot/bootx64.efi (that is from the root of the efi system partition), which is the default efi application.  So you could make that anything you wnat really. 

What I have, is gummiboot set up in that default position.  Then I have gummiboot set up to boot the kernel itself with the efi stub loader.  That way I only have to have a boot manager and not a loader.  If you really want to use uefi, I would recommend not using grub.  It is more complexity than is necessary since the kernel can now boot itself.

Edit: More info... the efi system partition needs to be ef00, and if you want it to acually be fat32, it needs to be 512MB.  I actually use the efi system partition as the boot partition itself (mounted to /boot).  By doing this, the kernel is installed to the esp automatically, and then all I have to do is have something that copies/moves the kernel to vmlinuz-linux.efi (so that it can be a uefi launchable application).  You should probably see the UEFI Bootloaders wiki page.  It has some pretty invaluable information as well as links to more information.  Also, rod's books has some pretty amazing uefi information.

Last edited by WonderWoofy (2012-10-30 05:48:11)

vee

Member

Registered: 2012-10-30

Posts: 2

Re: gpt btrfs and grub2, grub issue

Yay options; I did read about gummiboot and loading the grub config straight into a single file, as well as keeping the grub config on the uefi partition too, lots of options and I figured I'd stick with GRUB seeing as I've used it forever.

However, I just attempted the efibootmgr and encountered the use "modprobe uefivars" however this didn't work (seems I need to be booted via UEFI for this method to work) - only did quick research on this and will probably go with another method tomorrow.

Thanks for the input WonderWoofy; I'll tread on and post tomorrow my progress and if I have further questions (hope not).