# Show messages from the current boot journalctl -b -0
# Show all messages by a specific unit journalctl -u dbus
# Show all messages from the previous boot journalctl -b -1
# Show all messages by a specific executable journalctl /usr/lib/systemd/systemd
# Show all messages by a specific process journalctl _PID=1
# Show kernel ring buffer journalctl -k
# display from the most recent entry in system log (end) journalctl -e
# Shows all logs from current boot journalctl -b 0