.conf File — Configuration File

CONF is a generic configuration file extension widely used in Unix/Linux systems for daemon and service configuration. CONF files appear throughout Linux system administration — /etc/ contains numerous .conf files for system services including sysctl.conf (kernel parameters), resolv.conf (DNS configuration), fstab (filesystem mounts), logrotate.conf (log rotation), sudoers.conf (privilege escalation), and application-specific configurations for Apache, Nginx, MySQL, PostgreSQL, and others. The format varies by application but commonly uses key-value pairs, space or equals-sign separated, with comment lines starting with # or ;. Some .conf files use more structured formats with sections, blocks, or directive-based syntax. In the Python ecosystem, .conf files are used by Sphinx documentation (conf.py), while Supervisor uses a Windows INI-style .conf format. The convention of using .conf for configuration files is deeply embedded in Unix culture and the Filesystem Hierarchy Standard (FHS). Many .conf files in /etc/ are critical for system operation and require root privileges to modify. Configuration management tools like Ansible, Puppet, and Chef frequently manage .conf files across server fleets.