Introduction
In any Linux system, event logging is fundamental for monitoring behavior, diagnosing problems, and ensuring the integrity of the environment. The most traditional and widely adopted mechanism is the syslog system, which centralizes messages generated by the kernel, services, and applications in a structured format.
What is syslog?
Syslog is a protocol and a set of tools designed to capture, classify, and store system events. Each message includes a timestamp, the name of the host that generated it, a facility indicating the origin of the message, and a severity level reflecting its criticality.
History and evolution
The origin of syslog dates back to the 1980s, when it was implemented in the Berkeley Unix system as a simple daemon called syslogd. Over time, more advanced alternatives emerged such as rsyslog and syslog-ng, which add features like filtering based on regular expressions, TLS support, and writing to databases.
Main components
In a typical Linux installation we find several daemons that can fulfill the syslog role:
- syslogd: the original daemon, still present in some minimalist distributions.
- rsyslog: an improvement over syslogd with high performance, input and output modules, and
This post is also available in ESPAÑOL.