Chapter 36. Log Files

Chapter 36. Log Files

36.1. Locating Log Files
36.2. Viewing Log Files
36.3. Adding a Log File
36.4. Monitoring Log Files

Log files are files that contain messages about the system, including the kernel, services, and applications running on it. There are different log files for different information. For example, there is a default system log file, a log file just for security messages, and a log file for cron tasks.

Log files can be very useful when trying to troubleshoot a problem with the system such as trying to load a kernel driver or when looking for unauthorized log in attempts to the system. This chapter discusses where to find log files, how to view log files, and what to look for in log files.

Some log files are controlled by a daemon called syslogd. A list of log messages maintained by syslogd can be found in the /etc/syslog.conf configuration file.

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