Journalctl Niceties
Part of the systemd solution is the log manager journalctl -- which takes a while to get used to. I does provide some nifty features though.
You can list the times the machine has booted, with unique identifiers per boot:
journalctl --list-boots
Add an -n X to only list the last X boots; the last two boots on my machine right now
is thus:
IDX BOOT ID FIRST ENTRY LAST ENTRY
-1 5fdf88e99fc443368952110898c387d8 Tue 2026-03-17 07:47:16 CET Wed 2026-03-18 08:10:19 CET
0 4a374ebd43fc4260a02fcdb38f9d0b67 Wed 2026-03-18 08:11:31 CET Wed 2026-03-18 08:19:18 CET
Then, using the index you can get the system logs from just before the last boot by doing:
journalctl -b -1 -e
You may add the -p err flag to only get error level, and perhaps -k to only get kernel logs.
For ordinary applications (units) the -u parameter selects the unit -- specifying --follow mimics
the use of tail on ordinary log files -- and finally --since='10 min ago' lets you not get logs
since the beginning of time :-)
Example:
journalctl -u nginx --since='10 min ago' --follow
Will give you the last 10 minutes of the nginx log and tail for new log lines. Nify.