Security logging can easily become a volume problem. Modern environments generate logs from identity systems, cloud platforms, networks, endpoints, applications, databases and security tools.
Collecting everything is expensive and often unhelpful. Collecting too little leaves gaps when an incident needs to be investigated.
The right approach is to identify the events that matter, make sure they are retained reliably and connect them to monitoring that somebody is responsible for acting on.
Start with the questions you need to answer
Logging should support real operational and security questions.
Who signed in? Who changed a security policy? Which system made the connection? Was a privileged account used? When did a configuration change occur? Which data was accessed?
If a log source cannot help answer a meaningful question, it may not deserve the same retention and monitoring priority as a higher-value source.
Collect identity and authentication events
Identity logs are among the most valuable security data sources.
Collect successful and failed sign-ins, multi-factor authentication events, account lockouts, password resets, creation and deletion of accounts and changes to privileged group membership.
For cloud platforms, also capture role assumption, federation events and creation of long-lived credentials such as API keys where applicable.
Capture privileged and administrative activity
Changes made through cloud consoles, APIs and administrative tools should be auditable.
Control-plane logs can show who created a resource, changed a firewall rule, modified a policy, deleted a backup or altered logging itself.
These records are essential during incident investigation because they provide a timeline of administrative actions.
DNC’s Cyber Security services include security-control and logging reviews across cloud and enterprise environments.
Monitor network activity where it adds value
Network telemetry can help identify unexpected communication patterns, external access and lateral movement.
Useful sources can include firewall logs, flow logs, VPN events, load-balancer access logs and DNS activity.
The aim is not to store every packet indefinitely. It is to retain enough evidence to understand important communication paths and investigate suspicious behaviour.
Include endpoint and server events
Operating systems and endpoint security tools can provide visibility that cloud control-plane logs cannot.
Authentication, process execution, service changes, security alerts, malware detections and local privilege events may all be relevant.
Coverage should focus first on systems where compromise would have significant impact.
Log application security events
Applications should record events that are meaningful to their own security model.
These can include failed logins, privilege changes, sensitive transactions, administrative actions, unexpected input failures and access to high-value records.
Application logs become more useful when they include consistent timestamps, user identifiers and request or correlation IDs.
Do not overlook databases
Databases often contain an organisation’s most valuable information.
Logging may need to cover privileged connections, failed authentication, account changes, schema changes, audit-policy modifications and access to particularly sensitive data.
The level of database auditing should reflect risk because indiscriminate logging can create significant volume and performance overhead.
Monitor backups and recovery controls
Attackers increasingly target recovery capability as well as production systems.
Collect events for backup failures, deletion of recovery points, retention-policy changes and changes to backup permissions.
An organisation should know quickly if the controls it depends on for recovery have been weakened.
Include cloud security findings
Cloud-native security services can identify risky configurations, public exposure, vulnerable workloads and suspicious behaviour.
Those findings should feed a process that determines which ones require investigation and who owns remediation.
Simply enabling a security service does not provide protection if nobody reviews its output.
Protect the logs themselves
Logs should be treated as security evidence.
Access to them should be restricted, retention should be defined and deletion should be controlled.
Where practical, important logs should be stored in a location that is separate from the systems they describe so that a compromised workload cannot easily erase its own history.
Use consistent time
Accurate timestamps are fundamental during an investigation.
Systems should use reliable time synchronisation and logs should record timezone information consistently.
Without this, correlating events across cloud, network, application and database systems becomes much harder.
Choose retention based on need
There is no single correct retention period for every log source.
Requirements may be driven by regulation, contractual obligations, investigation needs and storage cost.
High-value audit logs may justify longer retention than verbose diagnostic logs.
Turn logs into useful alerts
Collecting data is only the first step.
Monitoring should focus on behaviours that deserve action, such as repeated failed privileged logins, unexpected administrator creation, security-policy changes, public exposure, disabled logging or abnormal outbound traffic.
Alerts should be tuned so that genuinely important events are not buried in noise.
Assign ownership
Every important alert needs an owner and a response path.
The organisation should know who receives the alert, what they are expected to check, when it should be escalated and how the event is documented.
DNC’s Corporate Architecture and Technology Services can help map monitoring responsibilities across internal teams and third-party suppliers.
What good looks like
A mature logging design captures identity, administrative, network, endpoint, application and data-layer events in proportion to their risk.
Logs are protected, retained for a defined period and used to generate a manageable set of actionable alerts.
Most importantly, the organisation knows who responds when those alerts fire.
Conclusion
Effective security monitoring is not measured by how many terabytes of logs are stored.
It is measured by whether the organisation can detect meaningful events, reconstruct what happened and respond quickly enough to reduce impact.
If you need help reviewing security logging or monitoring coverage, see DNC’s Cyber Security services or contact DNC.