Arch Linux

TinkerToadie

Member

Registered: 2023-03-17

Posts: 7

Boot hangup on "Loading initial ramdisk" after update & restic backup

Hey Archers!

I am running an Arch64 server with the hardened kernel and update on a daily basis.

> uname -a 
Linux archserver 6.14.9-hardened1-1-hardened #1 SMP PREEMPT_DYNAMIC Mon, 02 Jun 2025 20:56:08 +0000 x86_64 GNU/Linux

Everything worked fine for many months. Yesterday I did a remote restic backup to the server via sFTP. This also worked fine for the last 141 snapshots.
But this time it caused some hangup and I had to cold reboot.

Since then the boot process hangs at

“Loading initial ramdisk.”

The snapshots are stored on a HDD which is only mounted when I start the backup. So it is fully independent from the system root and boot directory which resides on a seperate SSD.

What I did so far (w/ checking the boot behaviour after every approach and no effect so far…):

(1) Updated (from <arch-chroot> environment):

> sudo arch-chroot /mnt/root
root> sudo pacman -Syu

(2) Added an <echo>-prompt to the <grub.cfg>:

echo    'Loading Linux linux-hardened ...' 
linux   /boot/vmlinuz-linux-lts root=UUID=fa7a634b-f09f-4798-9eb4-98177ad59d64 rw  loglevel=3 nomodeset 
echo    'Loading initial ramdisk ...' 
initrd  /boot/amd-ucode.img /boot/initramfs-linux-hardened.img
echo “Initramfs loaded.”

This prompt is actually reached every time, so I suppose the image is loaded.
But then the boot process hangs again.

(3) Check UUIDs especially for the root directory in <fstab> (from <arch-chroot> environment):

> cat /etc/fstab 
# Static information about the filesystems. 
# See fstab(5) for details. 

# <file system> <dir> <type> <options> <dump> <pass> 
# /dev/sdb2 
UUID="fa7a634b-f09f-4798-9eb4-98177ad59d64"     /               ext4            rw,relatime     0 1 

# /dev/sdb1 
UUID="15fa3d9c-abc9-4f20-8390-f74281322560"     none            swap            defaults        0 0 

# /dev/sda3  
UUID="18d2b4bc-564a-48be-9128-eff85b1d9135"     /home           ext4            rw,relatime     0 1

Excerpt from <blkid> in <arch-chroot> environment:

> blkid
/dev/sdc2: UUID="fa7a634b-f09f-4798-9eb4-98177ad59d64" BLOCK_SIZE="4096" TYPE="ext4" PARTUUID="ef918bb9-02" 
/dev/sdc3: UUID="18d2b4bc-564a-48be-9128-eff85b1d9135" BLOCK_SIZE="4096" TYPE="ext4" PARTUUID="ef918bb9-03" 
/dev/sdc1: UUID="15fa3d9c-abc9-4f20-8390-f74281322560" TYPE="swap" PARTUUID="ef918bb9-01"

The different device paths should not matter here since the drives are defined by their UUID, right?

(4) Booted with all installed kernels and also their fallback versions, i.e.

>ls -l /boot 
total 439500 
-rw-r--r-- 1 root root    153600 Mai 22 20:06 amd-ucode.img 
drwxr-xr-x 6 root root      4096 Jun  4 00:09 grub 
-rw------- 1 root root 119448200 Jun  3 13:02 initramfs-linux-fallback.img 
-rw------- 1 root root 119295638 Jun  3 13:01 initramfs-linux-hardened-fallback.img 
-rw------- 1 root root  15172900 Jun  3 13:00 initramfs-linux-hardened.img 
-rw------- 1 root root  15090497 Jun  3 13:02 initramfs-linux.img 
-rw-r--r-- 1 root root  15462912 Mai 31 11:08 vmlinuz-linux 
-rw-r--r-- 1 root root  15254016 Jun  3 10:22 vmlinuz-linux-hardened 

(5) Booted with & without <amd-microcode.img>:

Therefor I interactively changed the kernel parameters in the GRUB menu (1st entry, hit [e]) from

initrd  /boot/amd-ucode.img /boot/initramfs-linux-hardened.img

to

initrd /boot/initramfs-linux-hardened.img

(5) Installed <linux-lts> kernel from <arch-chroot> environment and booted with it:
   

> sudo arch-chroot /mnt/root

#> pacman -Syu linux-lts

#> grub-mkconfig -o /boot/grub/grub.cfg 
Generating grub configuration file ... 
Found linux image: /boot/vmlinuz-linux-lts 
Found initrd image: /boot/amd-ucode.img /boot/initramfs-linux-lts.img 
Found fallback initrd image(s) in /boot:  amd-ucode.img initramfs-linux-lts-fallback.img 
Found linux image: /boot/vmlinuz-linux-hardened 
Found initrd image: /boot/amd-ucode.img /boot/initramfs-linux-hardened.img 
Found fallback initrd image(s) in /boot:  amd-ucode.img initramfs-linux-hardened-fallback.img 
Found linux image: /boot/vmlinuz-linux 
Found initrd image: /boot/amd-ucode.img /boot/initramfs-linux.img 
Found fallback initrd image(s) in /boot:  amd-ucode.img initramfs-linux-fallback.img 
Warning: os-prober will not be executed to detect other bootable partitions. 
Systems on them will not be added to the GRUB boot configuration. 
Check GRUB_DISABLE_OS_PROBER documentation entry. 
Adding boot menu entry for UEFI Firmware Settings ... 
done

I will go with the LTS kernel in future anyways (for obvious reasons ;> ). However, boot still hangs.

Additional information

See the full <grub.cfg> here [pastebin.com]
Further system specs:
    * CPU: AMD Phenom II X6 1055T
    * Motherboard: ASUS M4A87TD EVO
    * RAM: 2x 2GB DDR3 1333Mhz PC3-10660 CL7-7-7-24
    * GFX: nVidia Geforce GTX 460

Every help on further debugging is much appreciated!

.toadie

Last edited by TinkerToadie (2025-06-04 09:35:31)

TinkerToadie

Member

Registered: 2023-03-17

Posts: 7

Re: Boot hangup on "Loading initial ramdisk" after update & restic backup

(6) Tried the following kernel parameters with the LTS kernel

as recommended here in the forums.

iommu=off
amd_iommu=off
acpi=off

Neither one alone nor all in combination did change anything.

EDIT: Maybe the topic should be moved to the "Kernel & Hardware" forum, I just got aware of that. Thank you mods!

Last edited by TinkerToadie (2025-06-04 12:56:41)