The importance of collecting and analyzing logs for threat detection and incident response.
Logging and monitoring are the cornerstones of a proactive security posture. You can't defend against what you can't see. Logging is the process of recording events that happen within an organization's systems and networks. These records, called logs, are generated by nearly every device and application: operating systems, firewalls, servers, databases, and more. A log entry typically contains information about what event occurred, who or what initiated it, when it happened, and its outcome. Monitoring is the process of continuously reviewing and analyzing these logs to detect potential security threats or operational issues. Given the sheer volume of logs generated in any modern environment, manual review is impossible. Instead, organizations use a Security Information and Event Management (SIEM) system. A SIEM aggregates log data from across the entire infrastructure into a centralized platform. It can then be used to analyze the data in real-time, correlate events from different sources, and generate alerts when activity matches a predefined rule indicating a potential security incident. For example, a SIEM could generate an alert if it sees a user log in from a new country, and then immediately afterward, there's a large data exfiltration from a sensitive database. Effective monitoring allows security teams to move from a reactive state (responding after a breach is discovered) to a proactive one, identifying and stopping attacks in their early stages. Logs are also indispensable for post-incident forensics, providing the evidence needed to understand how an attack happened, what its impact was, and how to prevent it from happening again.