ArchLabs Linux

When Arch rescues ArchLabs

This morning I updated the kernel, video driver, broadcom etc… and I forgot to regenerate the grub.cfg file, so when I rebooted BOUM! kernel panic.
I plugged my Archlinux usb drive and simply chroot to ArchLabs’ installation:
First list partitions:

lsblk
NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT
sda 8:0 0 119.2G 0 disk
├─sda1 8:1 0 256M 0 part /boot/efi
└─sda2 8:2 0 20G 0 part /
sdb 8:16 0 931.5G 0 disk
├─sdb1 8:17 0 8G 0 part [SWAP]
└─sdb2 8:18 0 396.1G 0 part /home
sr0 11:0 1 1024M 0 rom

Then mount them:

mount /dev/sda2 /mnt
mount /dev/sda1 /mnt/boot
mount /dev/sdb2 /mnt/home
swapon /dev/sdb1 # optional

Let’s chroot into

arch-chroot /mnt

So I could run:

grub-mkconfig -o /boot/grub/grub.cfg

Exit and unmount everything:

exit
umount -R /mnt

Now we can do so with another distro live-cd but we have to mount other parts of the system:

mount -t proc /proc proc/
mount --rbind /sys sys/
mount --rbind /dev dev/

source: https://wiki.archlinux.org/index.php/Chroot
Conclusion: Always have an Archlinux cd or flash drive to make my title possible: arch rescues archlabs.
ps: Manjaro has grub.cfg update in the kernel update procedure itself, so if you come from Manjaro don’t forget to do it manually and burn your usb-flash drive NOW!! :smile:

6 Likes

mount /dev/sda1 /mnt/boot is not correct, you have /boot/efi.
the next kernel update you will panic,now your system travels with / boot and not /boot /efi

No way, I have just rebooted after reading your answer and here I am 20 seconds later and I still have /boot/efi/EFI :smile:
I have just reloaded the grub config and not reinstall it so i’m fine and I can’t wait for the next update.

efi directory is a sub-directory of /boot that means it’s included and again if I have done wrong I couldn’t be able to boot back. Does Dobbie’s solution is the only one and are we exactly in the same situation ?