Straight to GRUB, Arch partition doesnt load

saltbringer · 2024-09-04 12:51:15

Have been running Arch for the past two months as my main distro. Have previous partitions with the OEM Windows install and my last distro Ubuntu. Recently, I rebooted and instead of my normal login screen, I get black screen grub> prompt. I can exit out and select either Ubuntu or Windows to boot into, but not my Arch install (hd0,pt9). Tried to tinker with the UEFI boot settings, but no go. Need help on how to proceed.

cryptearth · 2024-09-04 12:56:30

sounds like the esp wasn't mounted during a recent update
one way: boot an arch install media - arch-chroot into the system - make sure the esp is mounted correctly (may fix your fstab) - reinstall kernel which also triggers a recreation of the initramdisk - and check your grub.cfg
if somethings our of order recreate a new config with grub-mkconfig

saltbringer · 2024-09-05 12:33:08

Can I do any of this from GNU Grub? I get the impression that this grub prompt is associated with my Arch partition. But none of the usual Linux commands seem to work in here

https://www.linuxfoundation.org/blog/bl … 2-on-linux

Looks like it might work for me. But I'm not sure how to specify some of the things like lines 2 and 3 here:

grub> set root=(hd0,1)
grub> linux /boot/vmlinuz-3.13.0-29-generic root=/dev/sda1
grub> initrd /boot/initrd.img-3.13.0-29-generic
grub> boot

My Arch partition is (hd0,gpt9) so definitely root shouldn't be /dev/sda1. Dunno how to find the current vmlinuzband initrd.img files on my current install either

Last edited by saltbringer (2024-09-05 13:02:03)

cryptearth · 2024-09-05 14:02:41

again:

one way is to boot an arch install media

it maybe possible from grub rescue shell - but I'm no expert in helping with that
as for the root= parameter I would use a uuid

Head_on_a_Stick · 2024-09-05 14:16:50

saltbringer wrote:

I get the impression that this grub prompt is associated with my Arch partition

The "grub>" prompt indicates that GRUB has found it's modules and loaded but it cannot find any valid menuentries to present, this may be because grub.cfg is missing or is searched for in the wrong location; it may also be caused by a grub.cfg that lacks menuentries.

The `set` command (just by itself, no flags or arguments) from the "grub>" prompt should show where GRUB is looking for $configfile (grub.cfg).

saltbringer wrote:

Dunno how to find the current vmlinuzband initrd.img files on my current install either

For the vanilla kernel package Arch uses /boot/vmlinuz-linux and /boot/initramfs-linux.img, if you want to try those.

euromatlox · 2024-09-05 17:14:09

I recently had an issue that linux files were installed during an update to root partition's boot directory instead of boot partition. It did cause some strange behavior.

saltbringer · 2024-09-06 12:45:01

Head_on_a_Stick wrote:

saltbringer wrote:
I get the impression that this grub prompt is associated with my Arch partition
The "grub>" prompt indicates that GRUB has found it's modules and loaded but it cannot find any valid menuentries to present, this may be because grub.cfg is missing or is searched for in the wrong location; it may also be caused by a grub.cfg that lacks menuentries.
The `set` command (just by itself, no flags or arguments) from the "grub>" prompt should show where GRUB is looking for $configfile (grub.cfg).

Thanks. Is there a way to check/configure/remake my grub.cfg (Arch partition) from, say my Ubuntu partition? For example, I am in Ubuntu now, looking at the files on my Arch partition. I can see the vmlinuz and initramfs.img files, along with the grub.cfg.

#
# DO NOT EDIT THIS FILE
#
# It is automatically generated by grub-mkconfig using templates
# from /etc/grub.d and settings from /etc/default/grub
#

### BEGIN /etc/grub.d/00_header ###
insmod part_gpt
insmod part_msdos
if [ -s $prefix/grubenv ]; then
  load_env
fi
if [ "${next_entry}" ] ; then
   set default="${next_entry}"
   set next_entry=
   save_env next_entry
   set boot_once=true
else
   set default="0"
fi

if [ x"${feature_menuentry_id}" = xy ]; then
  menuentry_id_option="--id"
else
  menuentry_id_option=""
fi

export menuentry_id_option

if [ "${prev_saved_entry}" ]; then
  set saved_entry="${prev_saved_entry}"
  save_env saved_entry
  set prev_saved_entry=
  save_env prev_saved_entry
  set boot_once=true
fi

function savedefault {
  if [ -z "${boot_once}" ]; then
    saved_entry="${chosen}"
    save_env saved_entry
  fi
}

function load_video {
  if [ x$feature_all_video_module = xy ]; then
    insmod all_video
  else
    insmod efi_gop
    insmod efi_uga
    insmod ieee1275_fb
    insmod vbe
    insmod vga
    insmod video_bochs
    insmod video_cirrus
  fi
}

if [ x$feature_default_font_path = xy ] ; then
   font=unicode
else
insmod part_gpt
insmod btrfs
search --no-floppy --fs-uuid --set=root 45106c82-89ee-444d-9473-bda92ec394ad
    font="/@/usr/share/grub/unicode.pf2"
fi

if loadfont $font ; then
  set gfxmode=auto
  load_video
  insmod gfxterm
  set locale_dir=$prefix/locale
  set lang=en_US
  insmod gettext
fi
terminal_input console
terminal_output gfxterm
if [ x$feature_timeout_style = xy ] ; then
  set timeout_style=menu
  set timeout=5
# Fallback normal timeout code in case the timeout_style feature is
# unavailable.
else
  set timeout=5
fi
### END /etc/grub.d/00_header ###

### BEGIN /etc/grub.d/10_linux ###

Not really sure what to be looking for apart from root being set to the correct mountpoint (45106c82-89ee-444d-9473-bda92ec394ad appears to be correct, as it is the mount point for my Arch partition).

cryptearth · 2024-09-06 13:00:23

grub loading btrfs and load additional data from it looks somewhat wrong
but to get a working cfg you can chroot into arch from ubuntu: https://wiki.archlinux.org/title/Chroot - although I still recommend booting an arch install media

Head_on_a_Stick · 2024-09-06 18:29:16

saltbringer wrote:

Is there a way to check/configure/remake my grub.cfg (Arch partition) from, say my Ubuntu partition?

You can install the arch-install-scripts package in Ubuntu, which will provide arch-chroot(8) so you can follow that section of cryptearth's ArchWiki link (grub-mkconfig needs the API filesystems mounted to detect the drives).

saltbringer wrote:

I can see the vmlinuz and initramfs.img files

Are you using a separate /boot/ partition for Arch?

saltbringer wrote:

the grub.cfg

That contains no menuentries, which is strange, but it explains the "grub>" prompt. Did you try the `set` command from the "grub>" prompt? Did it confirm the Arch partition as the source of $configfile?

Arch Linux

#1 2024-09-04 12:51:15

Straight to GRUB, Arch partition doesnt load

#2 2024-09-04 12:56:30

Re: Straight to GRUB, Arch partition doesnt load

#3 2024-09-05 12:33:08

Re: Straight to GRUB, Arch partition doesnt load

#4 2024-09-05 14:02:41

Re: Straight to GRUB, Arch partition doesnt load

#5 2024-09-05 14:16:50

Re: Straight to GRUB, Arch partition doesnt load

#6 2024-09-05 17:14:09

Re: Straight to GRUB, Arch partition doesnt load

#7 2024-09-06 12:45:01

Re: Straight to GRUB, Arch partition doesnt load

#8 2024-09-06 13:00:23

Re: Straight to GRUB, Arch partition doesnt load

#9 2024-09-06 18:29:16

Re: Straight to GRUB, Arch partition doesnt load

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