Glossary · Automation software engineering and architecture
Logging
Also known as: Event logging, Application logging
German: Protokollierung
In software engineering, logging is the recording of events, states, errors and actions that occur while software runs, as timestamped entries in a log, so that behavior can be monitored, problems analyzed and actions traced afterward.
- Software engineering
In one sentence
Logging records timestamped events, states, errors and actions while software runs, for monitoring, fault analysis and traceability.
Example
The line controller logs every recipe change with timestamp, user, old and new values, and every communication fault with the affected device address.
Explained in context
Context cards connect this term with others to answer one question. Also in British English and German.
How it applies
- Engineering: Good logs are structured, use consistent severity levels, include context such as device, order or user, and carry synchronized timestamps. Too little logging makes faults impossible to analyze; too much hides the important entries and fills storage.
- Operation and security: Logs support fault analysis, performance monitoring and security monitoring. IEC 62443 requires security-relevant events to be logged. Protect logs against tampering and define retention periods; logs may contain personal data, which data protection rules apply to.
- Documentation: Document log locations, formats, severity levels and important messages, and explain how service staff export logs for support. Where logs serve as records, for example of parameter changes, they are part of the Audit trail and should be treated accordingly.
Logging vs. audit trail
A log records technical events for analysis. An Audit trail is a secure, complete record of who did what and when, often required for compliance. An audit trail can be implemented with logging, but it needs stronger guarantees of completeness and integrity.