Logs (Linux)

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Linux logs are save usually in /var/log folder. Most linux distribution uses syslog, syslog-ng or rsyslog software for logging or sending them to remote servers. Analytics and visualisation software such a Elasticsearch and Kibana can be used for log inspection.

Usage by Distribution:

Standard logs:

  • Debian/Ubuntu: /var/log/syslog
  • RHEL/Fedora: /var/log/message

SSH sessions logging:

  • Debian/Ubuntu: /var/log/auth.log
  • RHEL/Fedora: /var/log/secure


  • SUSE: /var/log/warn.log
/var/log/message – Where whole system logs or current activity logs are available.
/var/log/auth.log – Authentication logs.
/var/log/kern.log – Kernel logs.
/var/log/cron.log – Crond logs (cron job).
/var/log/maillog – Mail server logs.
/var/log/boot.log – System boot log.
/var/log/mysqld.log – MySQL database server log file.
/var/log/secure – Authentication log.
/var/log/utmp or /var/log/wtmp : Login records file.
/var/log/yum.log: Yum log files.


Rsyslogd supports queued operations to handle offline outputs. Official documentation: https://www.rsyslog.com/doc/v8-stable/configuration/index.html

Rsyslog Configuration[edit]

Default configuration files by Distribution:


See also https://stackoverflow.com/questions/30969435/where-is-the-docker-daemon-log/30970134#30970134 for further information about docker logs.


See also[edit]

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