
By default, newer systemd based linux systems now uses two logging services for the system logs:
systemd-journald, which is configured to only keep logs in memory
rsyslogd, which gets messages sent to it by systemd-journald (and others) and stores them on disk.
To view messages in the system journal, a tool called journalctl can be used. If used without any parameters it will show the full contents of the system journal, presented in a pager (by default less is used). The output of journalctl can be modified by using both options and filters. Options can be used to change the number of lines displayed, to turn on follow mode, change the...