Removing SystemD from Linux

Dec 31, 2024 · 3 min read | Linux

Systemd is great for standardization, but it is insanely bloated. Boot times average around 20 seconds when removing it and using a minimal init system will result in a boot time of only a few seconds. This is a guide on switching to OpenRC.

What do I lose?

Systemd has a LOT of functions and can do the following, but often we swap out to alternatives anyways.

Bootloader (Grub is the alternative)
Timers (cronie is still widely used instead)
Networkd (NetworkManager is almost universally used - same goes for resolved for dns resolution)
Auto mount (A few distros use this but often /etc/fstab is used instead)
journald (This I will miss… it is a fantastic system log tool)
logind (Alternative is elogind - You NEED a login daemon because without it you have to run Xorg as ROOT which only a crazy person would do.)
timedated ( universal date and time management)
udev (device manager and very useful for using rules to manage device without elevation. Ex. Managing backlight on a laptop)

Switch to OpenRC

The switch is very easy

sudo apt install openrc sysvinit-core
sudo reboot

After restart process is complete install the following packages to fill in any gaps missing with systemd no longer on the system:

sudo apt install elogind libpam-elogind orphan-sysvinit-scripts systemctl procps
sudo reboot

Source: https://lecorbeausvault.wordpress.com/2022/02/07/debian-switching-init-system-easily-openrc-sysvinit-runit/

Prevent Systemd from reinstalling

Create /etc/apt/preferences.d/systemd

Package: systemd
Pin: release *
Pin-Priority: -1
 
Package: *systemd*
Pin: release *
Pin-Priority: -1
 
Package: systemd:i386
Pin: release *
Pin-Priority: -1

APT-Mark holds

sudo apt-mark hold libsystemd0

Systemd vs OpenRC Commands

This is a comparison of the different init systems and run commands.

Source: https://wiki.archlinux.org/title/OpenRC#Usage

SystemD	SysVinit	OpenRC	Description
systemctl list-units	rc.d list	rc-status	List running services status
systemctl –failed		rc-status –crashed	Check failed services
systemctl –all		rc-update -v show	Display all available services.
systemctl (start, stop, restart, status) daemon.service	rc.d (start, stop, restart) daemon	rc-service daemon (start, stop, restart, status)	Change service state.
systemctl (enable, disable) daemon.service	chkconfig daemon (on, off)	rc-update (add, del) daemon	Turn service on or off.
systemctl daemon-reload	chkconfig daemon –add		Create or modify configuration.

Creating an OpenRC Service/Daemon

Official Manual page: https://github.com/OpenRC/openrc/blob/master/service-script-guide.md

Create a service script here: /etc/init.d/mydaemon

#!/sbin/openrc-run

command="/usr/sbin/mydaemon"
command_args="-c /etc/mydaemon.conf"
command_user="user:group"
description="super essential service"
pidfile="/var/run/mydaemon.pid"

depend() {
  need localmount
  use logger
}

checkconfig() {
  ...
}

start_pre() {
  # Prevent of double check
  if [ "${RC_CMD}" != "restart" ] ; then
    checkconfig || return $?
  fi
}

stop_pre() {
  if [ "${RC_CMD}" = "restart" ] ; then
    checkconfig || return $?
  fi
}

No Video Planned

Let me know below if you would like a video on this topic.

#Systemd