OpenRC, an alternative to systemd

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OpenRC is an init system maintained by the Gentoo developers. OpenRC is a dependency based init system that works with the system provided init program, normally sysvinit. It is not a replacement for sysvinit.

It can be used as an alternative to systemd, for users that like more control over their system and do not want all the features that systemd provides and automatically activates.

Installation

OpenRC is available from the the Manjaro repositories. It can be installed as:

sudo pacman -S openrc-base

The output of the above command looks like the following:

$ sudo pacman -S openrc-base
:: There are 10 members in group openrc-base:
:: Repository community
   1) cronie-openrc  2) cryptsetup-openrc  3) dbus-openrc
   4) device-mapper-openrc  5) dhcpcd-openrc  6) glibc-openrc
   7) inetutils-openrc  8) lvm2-openrc  9) mdadm-openrc  10) openrc-core

Enter a selection (default=all): 
resolving dependencies...
looking for inter-conflicts...
:: openrc-core and systemd-sysvcompat are in conflict. Remove systemd-sysvcompat? [y/N] y

Packages (12): systemd-sysvcompat-212-3 [removal]  sysvinit-2.88-15
               cronie-openrc-20140614-1  cryptsetup-openrc-20140614-1
               dbus-openrc-20140614-1  device-mapper-openrc-20140614-1
               dhcpcd-openrc-20140614-1  glibc-openrc-20140614-1
               inetutils-openrc-20140614-1  lvm2-openrc-20140614-1
               mdadm-openrc-20140614-1  openrc-core-0.12.4-16

Total Download Size:    0.22 MiB
Total Installed Size:   1.19 MiB

:: Proceed with installation? [Y/n]

After installing the openrc-base package group, OpenRC should boot by default instead of systemd. Note that it will boot to a command line, as the service for a graphical display manager has not yet been installed.

On installing openrc-base, you may get messages like:

run 'rc-update add dbus default'
run 'rc-update add cronie default'

Running these command(s) adds the service(s) to the specified runlevels. For example if you run:

sudo rc-update add dbus default

Then the dbus service would be added to the default runelevel and would automatically be started at boot.

dbus (system message bus) and cronie (for cron) are some common services that can be enabled.

Additional packages

Display Manager

To boot to a graphical display manager, install the displaymanager-openrc package, enable the xdm service, and edit the /etc/conf.d/xdm file to specify your display manager. For example, to use lightdm, change the line

DISPLAYMANAGER="xdm"

to

DISPLAYMANAGER="lightdm"

Note:

lightdm and a lightdm-greeter should be installed to use lightdm as display manager. A guide is available on the forums.

An alternative to lightdm that I find simpler is LXDM. However the version in the repos does not automatically start a ck-session on login; alternative lxdm-consolekit from the AUR can be used.

For more info about consolekit, have a look at the Consolekit section.

Audio (ALSA)

The alsa-utils-openrc package can be installed. After installing it, run:

sudo rc-update add alsasound default

to automatically start alsa at boot.

Network Manager

By default dhcpcd is enabled via netifrc. However if you use Wifi to connect to the internet, or need a graphical network applet, then networkmanager-openrc can be installed.

networkmanager-openrc replaces the normal networkmanager package in the repos. Also, it requires consolekit and polkit-consolekit, which replaces the normal polkit from the repos.

Consolekit

The consolekit-openrc package can be installed. Consolekit supports multi-user setups, mounting of partitions by unauthorized users, etc. See the Gentoo-Wiki for more details.

Only caveat of installing consolekit is that it requires polkit-consolekit, which conflicts with the normal polkit; so if you boot to systemd you wont be able to mount partitions if you are not in the storage group.

However using the command line, or as root user, one can mount any partition or perform most functions that are made available to the normal user via polkit. See the Arch-wiki for more details.

Consolekit also allows a normal (non-root) user to shutdown or restart the system if the desktop environment supports it.

See the Using Consolekit section on how to install and for more info.

openrc-desktop

The openrc-desktop package group can be used to install most of the above desktop related packages in one go. For example:

$ sudo pacman -S openrc-desktop
:: There are 6 members in group openrc-desktop:
:: Repository community
   1) acpid-openrc  2) alsa-utils-openrc  3) avahi-openrc  4) consolekit-openrc
   5) displaymanager-openrc  6) gpm-openrc

Enter a selection (default=all): 
resolving dependencies...
looking for inter-conflicts...

Packages (6): acpid-openrc-20140614-1  alsa-utils-openrc-20140614-1
              avahi-openrc-20140614-1  consolekit-openrc-20140614-1
              displaymanager-openrc-20140614-1  gpm-openrc-20140614-1

Total Installed Size:   0.12 MiB
Net Upgrade Size:       0.00 MiB

:: Proceed with installation? [Y/n] 

Others

ACPI

For handling acpi events, acpid-openrc can be installed and enabled (see this for more details on acpid).

Logging

For logging, a logger can be chosen from metalog-openrc, syslog-ng-openrc, and rsyslog-openrc, by installing the package and enabling its respective service.

Suspend/Hibernate

To suspend and hibernate via the command line, pm-utils can be installed. You may also need the upower-pm-utils package if suspend and hibernate does not work. See the troubleshooting section for some issues you may face.

Note

If you were using plymouth before, then you need to edit /etc/mkinitcpio.conf and remove the plymouth hook, as plymouth does not work correctly with OpenRC. The hooks line should look like:

HOOKS="base udev autodetect modconf block resume filesystems keyboard keymap fsck"

After that would need to regenerate the initrd as:

sudo mkinitcpio -p linux<version>

For example,

sudo mkinitcpio -p linux314

Configuration

Adding or Removing services

Services can be added to startup with:

sudo rc-update add <service>

A service can be removed from startup with:

sudo rc-update del <service>

Check running services

To check what services are running, one can type:

rc-status

Start / stop / restart services

To start / stop / restart services immediately, the rc-service command can be used. For example:

sudo rc-service networkmanager restart

Some common services

To enable printing support, the cups-openrc package can be installed. For example,

$ sudo pacman -S cups-openrc
resolving dependencies...
looking for inter-conflicts...

Packages (1): cups-openrc-20141014-1

Total Installed Size:   0.01 MiB
Net Upgrade Size:       0.00 MiB

:: Proceed with installation? [Y/n] 

The service for it is cupsd.

$ sudo rc-service cupsd start
* Starting cupsd ...                                                                                                       [ ok ]

For ssh, the openssh-openrc package can be installed.

The service for it is named sshd.

Tip: All services present can be listed with the rc-service --list command.

Using Consolekit

Additionally, if not already done, consolekit can be installed to perform root actions like shutting down or restarting system as non-root user from your Desktop Environment.

Consolekit can be installed in the following way:

sudo pacman -S consolekit-openrc

The output looks like the following:

$ sudo pacman -S consolekit-openrc
[sudo] password for aaditya: 
resolving dependencies...
looking for inter-conflicts...
:: polkit-consolekit and polkit are in conflict. Remove polkit? [y/N] y

Packages (5): consolekit-0.4.6-4  js185-1.0.0-2  polkit-0.112-2 [removal]
              polkit-consolekit-0.112-2  consolekit-openrc-20140614-1

Total Download Size:    1.90 MiB
Total Installed Size:   10.67 MiB
Net Upgrade Size:       9.08 MiB 

:: Proceed with installation? [Y/n] 

After installing it can be enabled with sudo rc-update add consolekit and would be activated after a reboot. To check that consolekit is running and a ck-session was started, the following command can be used:

ck-list-sessions

The output looks like the following:

Session1:
	unix-user = '1000'
	realname = 'Aaditya Bagga'
	seat = 'Seat1'
	session-type = 
	active = TRUE
	x11-display = ':0'
	x11-display-device = '/dev/tty7'
	display-device = 
	remote-host-name = 
	is-local = TRUE
	on-since = '2014-06-15T13:29:58.652929Z'
	login-session-id = 

If you are not getting any output, then maybe a ck-session is not being started by your display manager.

To start a ck-session and X session from the command line following syntax could be used:

ck-launch-session <session-name>

For example,

ck-launch-session startxfce4

Some gotcha's

Display managers that are known to work with consolekit are lightdm, lxdm (via lxdm-consolekit), and kdm (via kdebase-workspace-consolekit). Have a look at the Display Manager section for more info.

If you start a graphical session from the command line, this forum post may be of some help.

If you use Openbox or another Window Manager along with oblogout, then oblogout-consolekit from the AUR can be used for having a graphical logout interface.

Replacing systemd with eudev (advanced users)

With OpenRC being used as init system, the role of systemd is reduced to that of a udev provider, and for compatibility reasons.

eudev, developed by the Gentoo folks, can be used as replacement. Note that removing systemd could cause some incompatibilities with existing software.

The steps to install eudev are as follows:

sudo pacman -S eudev-openrc eudev-systemdcompat

The output looks like the following:

$ sudo pacman -S eudev-openrc eudev-systemdcompat
resolving dependencies...
looking for inter-conflicts...
:: eudev-systemdcompat and systemd are in conflict. Remove systemd? [y/N] y
:: eudev-systemdcompat and libsystemd are in conflict. Remove libsystemd? [y/N] y

Packages (6): eudev-1.9-1  libeudev-1.9-1  libsystemd-212-2 [removal]
             systemd-212-2 [removal]  eudev-openrc-20140712-1
             eudev-systemdcompat-215-1

Total Download Size:    0.93 MiB
Total Installed Size:   6.38 MiB
Net Upgrade Size:       -10.84 MiB

:: Proceed with installation? [Y/n] 

After the above steps systemd would be uninstalled and replaced by eudev and its counterparts.

Note the optional dependencies for eudev:

Optional dependencies for eudev
   upower-pm-utils: pm-utils support

The upower-pm-utils package can be installed in order to be able to suspend and hibernate the system.

Possible issues

After uninstalling systemd, I could not login to my xfce4-session, as it was complied for systemd. Hence I had to install xfce4-session-consolekit from the AUR to get it working.

I also had to recompile xfce4-power-manager against upower-pm-utils to get it working (available in the AUR as xfce4-power-manager-upower).

Some packages depend on systemd components like systemd-tmpfiles and systemd-sysusers in their post install tasks; the openrc-systemdcompat package from the AUR can be installed to compensate for these missing components.

Troubleshooting

Boot logs

The boot logs for OpenRC are stored in /var/log/rc.log

Get warning at shutdown

If at shutdown there is a message like:

WARNING: /usr/lib/rc/cache is not writable!

Then this directory can be created as:

sudo mkdir /usr/lib/rc/cache

Error about /etc/sysctl.conf not found

It can be created with:

sudo touch /etc/sysctl.conf

Enable Swap (for GPT partitions)

If you were using systemd on a GPT partitioned hard disk, then you may need to enable swap via /etc/fstab. This is so because systemd handled swap automatically on GPT partitions, and gave error if it was mounted via fstab.

I added the following entry to my /etc/fstab

# /dev/sda10
UUID=0c3e9434-bc5c-461c-a5e4-4e9fe5f9a149	swap	swap	sw	0	0

Using tmpfs

systemd used to set a tmpfs by default; to set it manually via /etc/fstab, the following lines can be added:

tmpfs		/tmp		tmpfs   nodev,nosuid          	0  	0

See the Arch Wiki for more details.

Module auto-loading

For OpenRC, the modules to be loaded at boot are specified in /etc/conf.d/modules rather than being present as individual files in /etc/modules-load.d

The required modules can be manually moved over. An example /etc/conf.d/modules file looks like the following:

# You should consult your kernel documentation and configuration
# for a list of modules and their options.

modules="vboxdrv"

Setting hostname

If your hostname is being displayed as localhost even if there a different hostname in /etc/hostname, then you probably need to change your hostname in /etc/conf.d/hostname

Setting keymap

The keymap for the console can be set via editing /etc/conf.d/keymaps.

For X11 (graphical part of the system), it can be set via /etc/X11/xorg.conf.d/20-keyboard.conf

For more information have a look at the Gentoo wiki (with the difference that in Arch/Manjaro the keymaps are stored in /usr/share/kbd/keymaps [1]).

Setting Hardware clock

Can be done by editing /etc/conf.d/hwclock

Shutting down / rebooting

To shutdown the system, the poweroff command can be used.

Similarly to reboot, the reboot command can be used.

X does not start from a virtual terminal

With Xorg-1.16, Arch Linux decided to make X rootless using systemd-logind [2]. This means that using startx from a virtual terminal will possibly not work for users of OpenRC init system.

The workaround is to create a file /etc/X11/Xwrapper.config with the contents:

# Xorg.wrap configuation file
needs_root_rights = yes

Reference: Arch forum

Input devices not working

With eudev-3.0, a new input group was introduced; you could try adding your user to it.

sudo gpasswd -a <user> input

Reference: https://github.com/gentoo/eudev/issues/107

MySQL service not working

See: https://forum.manjaro.org/index.php?topic=19131.msg182573#msg182573

Further Reading

The Arch Wiki

OpenRC on Arch Linux

Support

Following is a link to this page's forum counterpart where you can post any related feedback: [3]