11 - Tail -f
Note: Just a command-line exercise.
The Problem: You need to see new log entries as they happen in real-time, but opening the file over and over is tedious.
The Solution: tail -f ("follow") keeps the file open and prints new lines as they are written.
Objective
Watch a log file in real-time.
How-to
Follow a File
bash
tail -f /var/log/syslogPress Ctrl+C to stop.
Use Cases
- Debugging a crashing server:
tail -f /var/log/nginx/error.log - Watching application output:
tail -f app.log
Related Exercises
- 12 - Journalctl - Systemd logs (the modern way)