log level
also: severity level, syslog level, priority level
A classification system that assigns severity to log messages, ranging from debug (lowest) to emergency (highest), allowing you to filter and prioritize which events get recorded.
Log levels are standardized severity ratings used by logging systems to categorize messages. The standard syslog levels, from lowest to highest severity, are: DEBUG, INFO, NOTICE, WARNING, ERROR, CRITICAL, ALERT, and EMERGENCY. Each message is tagged with a level indicating how serious the event is.
By setting a log level threshold, you control which messages actually get recorded or displayed. For example, if you set a service to log at WARNING level, it will record warnings, errors, critical alerts, and emergencies—but ignore debug and info messages. This reduces log noise and helps focus attention on genuinely important events.
Most Linux services and the systemd journal support log level configuration. You might see it in configuration files like /etc/rsyslog.conf or controlled via commands like journalctl -p warning to view only warning-level and above messages.