# By unit
journalctl -u sshd.service
# Extended logs
journalctl -u sshd.service -x
# go to end of log
journalctl -e
# Follow logs
journalctl -e -f
# By timestamp
journalctl --since today
# By executable
journalctl /sbin/sshd
# Kernel messages only
journalctl -k
# By user
journalctl _UID=1008
# By level/priority (emerg (0), alert (1), crit (2), err (3), warning (4), notice (5), info (6), debug (7)
journalctl -p 0
journalctl -p 0..4
# Disk usage
journalctl --disk-usage