Accesslog

Accesslog is a term used to describe a log that records access events to a resource or service. It provides a historical record of who accessed what and when, and is used for security auditing, troubleshooting, performance analysis, and capacity planning. The concept applies across web servers, application services, databases, and network devices. In many configurations, the file is named access.log or access_log, and the generic term “access log” is often used interchangeably with accesslog.

In web servers, an access log records each HTTP request. Typical fields include the client’s IP address, the remote user (if any), the timestamp, the request line (method, path, and protocol), the response status code, and the size of the response. Many implementations also log the referer and the user agent. Two widely used formats are the Common Log Format and the Combined Log Format, though many systems support custom fields.

Examples of systems that generate access logs include web servers such as Apache and Nginx, reverse proxies, application servers, and certain database or file services. Logs are often rotated and stored locally, or forwarded to centralized logging infrastructure via syslog, journald, or dedicated log shippers. Retention policies and rotation schedules vary by environment and regulatory requirements.

Privacy and security considerations are important, as access logs can reveal IP addresses, URLs, and other potentially sensitive information. Access controls, data minimization, anonymization, and compliance with applicable laws should guide logging practices. Analyzing access logs supports monitoring, anomaly detection, and forensic investigations, and is commonly complemented by modern log analytics and SIEM tools.