How to Use journalctl to Read Linux System Logs

Troubleshoot Linux servers with journalctl — the systemd journal log viewer.

Step 1: View Service Logs

Run journalctl -u nginx to see logs for a specific service.

Step 2: Filter by Time and Priority

Use --since "1 hour ago" and -p err to filter errors from the last hour.

Step 3: Follow Live Logs

Run journalctl -f -u servicename to tail logs in real time.

journalctl -b -1   # previous boot logs
journalctl --disk-usage

Terminal screenshots are original illustrations created for Gnome IT Solutions (blog.gnomeitsolutions.com).