How to tell journald to re-read its configuration?

To control running services with systemd, use the systemctl utility. This utility is similar to the service utility provided by SysVinit and Upstart. Among others:

• systemctl status systemd-journald indicates whether the service is running and additional information if it is.
• systemctl start systemd-journald starts the service (systemd unit).
• systemctl stop systemd-journald stops the service.
• systemctl restart systemd-journald restarts the service.
• systemctl reload systemd-journald reloads the service's configuration if possible, but will not kill it (so no risk of a service interruption or of disrupting processing in progress, but the service may keep running with a stale configuration).
• systemctl force-reload systemd-journald reloads the service's configuration if possible, and if not restarts the service (so the service is guaranteed to use the current configuration, but this may interrupt something).
• systemctl daemon-reload reloads systemd's own configuration.

systemctl restart systemd-journald does the trick.

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