Loglar

Loglar are records created by software, operating systems, networks, and users that document events and state changes over time. They are used for debugging, performance monitoring, security auditing, and compliance.

Common types include application logs, system logs, security logs, access logs, audit logs, and transaction logs. Entries typically include a timestamp, severity level, source component, and a human-readable message; many also carry identifiers, user context, and metadata.

Logs can be stored in several formats. Plain text is easy to read, while structured formats such as JSON and XML enable machine parsing. Standard formats include the Common Log Format for web servers, syslog for network devices, and the Windows Event Log.

Logs are often collected and centralized to enable search and analysis. Common practices include rotation and retention policies, redaction of sensitive data, and the use of log management tools such as Fluentd, Logstash, Elasticsearch, Splunk, and Graylog. Automated analysis can detect anomalies and trigger alerts.

Security and privacy considerations are important because logs may contain sensitive information. Organizations implement access controls, encryption at rest and in transit, integrity protection, and data minimization to comply with regulations such as GDPR and HIPAA.

Best practices include consistent, structured logging; standardized severity levels; avoiding leakage of secrets; providing enough context to diagnose issues; and clear retention policies. The main challenges are high volume, noisy data, storage costs, and protecting log integrity from tampering.