# All log entries for postfix journalctl _UID=`id -u postfix` --no-pager # Or journalctl _SYSTEMD_UNIT=postfix@-.service journalctl _SYSTEMD_UNIT=ssh.service journalctl -u ssh.service journalctl -u ssh.service -u postfix@-.service
# Yesterday's log entries journalctl _UID=`id -u postfix` -S yesterday -U today # OR journalctl -u postfix@-.service -S yesterday -U today
This does NOT work!
journalctl _SYSTEMD_UNIT=postfix.service
By Duration/Time
# Today's log entries journalctl _UID=`id -u postfix` -S today # Since 5 minutes ago journalctl -u postfix@-.service --since "5 minutes ago" # Other e.g. journalctl -u postfix@-.service --since "1 hour ago" journalctl -u postfix@-.service --since "2 days ago" journalctl -u postfix@-.service --since "2023-11-12 23:15:00" --until "2023-11-12 23:20:00"
# Tail log entries journalctl _UID=`id -u postfix` -f # Tail only last 50 lines journalctl -u postfix@-.service -n 50 --since "1 hour ago" # In Reverse journalctl -r -u postfix@-.service -n 50 --since "1 hour ago"
# Filter by priority journalctl -r -u postfix@-.service -n 50 --since "1 hour ago" -p "emerg".."warning"
Levels are: ● 0 or “emerg”, ● 1 or “alert”, ● 2 or “crit”, ● 3 or “err”, ● 4 or “warning”, ● 5 or “notice”, ● 6 or “info”, ● 7 or “debug”
# Mail log journalctl -u postfix.service --flush --rotate --vacuum-time=1s # All logs? journalctl --flush --rotate --vacuum-time=1s