Switching Artix Linux from OpenRC to runit: Step‑by‑step Guide

Desired outcome

Replace the OpenRC init system with runit on an existing Artix Linux installation, ensuring that the system boots successfully and essential services are supervised by runit.

Prerequisites

• An installed Artix Linux system currently using OpenRC as the init system.
• Root access (or ability to use sudo).
• Synchronized Pacman databases (sudo pacman -Sy).
• Working network connectivity to download packages from the Artix repositories.
• A bootloader that supports adding custom kernel entries (GRUB is assumed).

Procedure

1. Install the runit collection and related bootloader support:

   sudo pacman -S artix-runit artix-runit-boot

   The artix-runit meta‑package provides the runit service collection; artix-runit-boot adds a GRUB entry for booting with runit as PID 1.

2. Enable the runit boot entry:

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

   This regenerates the GRUB configuration and should add a menu entry titled something like “Artix Linux, with runit”. Verify its presence in the GRUB menu before rebooting.

3. Disable OpenRC services to avoid conflicts:

   List all enabled OpenRC services and disable them:

   sudo rc-update show | grep -v '^\s*$' | awk '{print $1}' | while read svc; do sudo rc-update del $svc default; done
   

   This removes the services from the OpenRC default runlevel, preventing them from being started by OpenRC if the system inadvertently falls back to it.

4. Reboot and select the runit entry:

   Restart the machine. At the GRUB screen, choose the entry that mentions runit. The system should boot with runit as PID 1.

5. (Optional) Remove OpenRC packages after verification:

   Only after confirming that runit is working correctly, you may uninstall the OpenRC meta‑package:

   sudo pacman -Rns artix-openrc
   

   Keep the package installed until you have verified that all essential services are running under runit.

Expected checks

1. Verify the init process:

   After login, run:

   ps -p 1 -o comm=

   The output should be runit.

2. Check a supervised service:

   For a common service such as dhcpcd:

   sv status dhcpcd

   Expected output includes a line indicating the service is up (or down if intentionally stopped) and shows the supervision directory under /etc/runit/sv.

3. Look for init‑related errors:

   Examine the boot journal:

   journalctl -b | grep -i runit

   No fatal errors should appear; any warnings about missing service directories should be investigated before proceeding.

Recovery options

If the system fails to boot or essential services are missing:

1. Boot from an Artix Linux live ISO.
2. Mount the root partition (e.g., sudo mount /dev/sda2 /mnt) and any separate boot/efi partitions.
3. Chroot into the installed system:

sudo arch-chroot /mnt

4. Re‑enable the OpenRC boot entry by reinstalling the OpenRC meta‑package and regenerating GRUB:

pacman -S artix-openrc
 grub-mkconfig -o /boot/grub/grub.cfg

5. Exit the chroot, unmount, and reboot. The system should now boot using OpenRC.
6. Once OpenRC is functional, you can revisit the runit switch, ensuring that equivalent runit service directories exist for any services you rely on.

Limitations and notes

• Some packages provide only OpenRC init scripts; equivalent runit service directories may need to be created manually or obtained from the artix-runit repository.
• Removing artix-openrc before verifying runit can leave the system unbootable if a required service lacks a runit equivalent.
• The procedure assumes GRUB as the bootloader; other bootloaders (e.g., systemd‑boot, EFISTUB) require analogous steps to add a runit kernel entry.