Linux Logs Explained: Key Files, Commands, and Debugging Techniques

Linux logs are system-generated records stored primarily in the /var/log directory, capturing events related to authentication, kernel activity, web servers, and general system behavior. Engineers use commands like tail, cat, less, and grep to read and filter log files, with tail -f being especially useful for real-time monitoring on production servers. Modern Linux systems running systemd offer journalctl as a unified log management tool, supporting service-specific queries, live streaming, and time-based filtering. Log rotation, handled automatically by the logrotate utility, prevents disk space exhaustion by compressing or deleting older log files. Proficiency in reading logs is considered a foundational skill in Linux troubleshooting, DevOps, and system administration.