Here's an excerpt from my cheat sheet: # Output all logs since boot journalctl # Follow all logs in real time journalctl -f # Output logs f

Here's an excerpt from my cheat sheet: # Output all logs since boot journalctl # Follow all logs in real time journalctl -f # Output logs for a given systemd unit journalctl -u $unit # Combine follow and unit flags to follow logs for a given systemd unit # Easy to remember: You are saying F*** U to a broken piece of software journalctl -fu $unit # Output kernel logs journalctl -k # Follow kernel logs journalctl -fk # Tip: Use -b flag to see logs from previous boot cycles # Learn more, including advanced filtering and formatting man journalctl You can also add that configtest command as an ExecStartPre to the unit, and it will run that before starting nginx and optionally fail early if it finds an error.