Systemd (en)

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systemd is the init system used on the Dreambox since OE 2.2. The system starts, monitors and stops services. The activities of the services are also logged by this system. It can also be used to configure the system and to mount devices. Compared to the older SysVinit system, the systemd is also faster because it can start services simultaneously. Systemd is backwards compatible for SysVinit scripts, which are still used on the Dreambox.

Systemctl

Systemctl is the main program of systemd. The command starts, stops, enables, disables services and can display status information. General configuration files can be found in /etc/systemd. Config files which are created manually or belong to services can be found in the directory /etc/systemd/system, or /lib/systemd/system.

Important parameters for systemctl which are used to manage services are: start, stop, restart, enable, or disable. In this article the management of services is explained with some examples.

The following examples can be used with enigma2 as $service_name.

Show information about systemctl

systemctl --help

Start service

systemctl start $service_name

Stop service

systemctl stop $service_name

Disable service

The following command disables a service. After a restart, the service will no longer be startet.

systemctl disable $service_name

Enable service

systemctl enable $service_name

Show service status

systemctl status $service_name

Journalctl

An additional important command is journalctl. It can be used to read, filter, export or check log entries of systemd. The output in the terminal can be stopped with Ctrl+c.

Show options for journalctl

journalctl --help

Show system journal

The command will show all information concerning system. With PgUP and PgDn the journal can be browsed.

journalctl

If the actual information should be displayed immediately, use the option -f for follow.

journalctl -f

Show journal for a service

The command shows the information for a specific service.

journalctl -f -u $service_name

Write journal in a file

The command saves the information in a file.

journalctl -f -u $service_name >> /tmp/journal.log

Other interesting commands

Change host name

Changes the name (/etc/hostname) of the Dreambox, important if you use 2 identical Dreambox models.

hostnamectl set-hostname $new_name

Set system time / date

To see the time / date.

timedatectl status

To set the time / date.

timedatectl set-time "yyyy-MM-dd hh:mm:ss"

Show device status

systemctl /dev/$devicename status

Reboot Dreambox

systemctl reboot

Shut down Dreambox

systemctl poweroff