Understanding Sumo Logic Architecture

Log Ingestion and Collectors

Sumo Logic collects data through installed collectors (hosted or installed) and sources (local file, syslog, AWS CloudTrail, Kubernetes, etc.). Most ingestion problems originate from misconfigured sources, network issues, or source category mismatches.

Search Language and Query Execution

The query engine supports a proprietary language optimized for streaming data. Performance depends on time range, filters, and data volume. Slow queries often result from broad time ranges, unindexed fields, or complex joins.

Common Sumo Logic Issues

1. Logs Not Appearing in the Dashboard

Usually due to incorrect source configuration, bad sourceCategory tags, or delays in ingestion caused by throttling or network disconnects.

2. Field Extraction Rules (FERs) Not Working

Occurs when regular expressions are misconfigured, conflicting FERs are applied, or logs are in inconsistent formats.

3. Scheduled Searches or Alerts Not Firing

May happen due to filters excluding all results, time zone mismatches, or misconfigured thresholds in alert rules.

4. Log Ingestion Lag or Drops

Triggered by high volume spikes, collector bottlenecks, agent version incompatibilities, or excessive regex-based parsing.

5. Query Performance Degradation

Caused by wide time ranges, wildcard searches, unindexed fields, or misuse of aggregation operators.

Diagnostics and Debugging Techniques

Verify Log Source and Collector Health

Check the Collection tab for source status, heartbeat timestamps, and ingestion volume. Use:

_sourceCategory=your/source/category | count by _collector

Test FERs Using Live Tail

Use Live Tail to view logs in real time and validate regex against the actual log structure. Adjust FERs interactively using test strings.

Inspect Alert Logs

Check the Alert History tab for failed executions or empty result sets. Compare scheduled search filters with real-time queries.

Monitor Ingestion Metrics

Use the sumologic_collector app to monitor events/sec, failed requests, and agent restarts.

Profile Query Bottlenecks

Use the Query Performance Analyzer to detect time-intensive stages. Simplify filters, reduce time range, and avoid wildcarding indexed fields.

Step-by-Step Resolution Guide

1. Restore Missing Logs in Dashboards

Ensure correct sourceCategory is used in query and source definition. Verify firewall settings if using Installed Collectors.

2. Repair FER Failures

Reorder or disable conflicting FERs. Use concise and greedy regex patterns. Confirm field naming conventions match expected format.

3. Debug Silent Alerts

Re-run the scheduled query manually. Adjust filters and time ranges to confirm expected matches. Review alert frequency and threshold logic.

4. Address Ingestion Lag or Drops

Scale collector infrastructure, throttle log sources, and compress log streams. Upgrade Installed Collectors to latest version for performance enhancements.

5. Optimize Query Execution

Use indexed fields early in the query. Reduce time range to ≤1h when debugging. Break down complex queries into chained searches for better performance visibility.

Best Practices for Sumo Logic Reliability

  • Tag all sources with consistent and structured sourceCategory hierarchies.
  • Use scheduled views to pre-aggregate high-cardinality data and improve search responsiveness.
  • Limit regex use in FERs and centralize them for global visibility and consistency.
  • Set up ingestion alerts for early detection of log drops or collector errors.
  • Use partitioned indexes for large datasets to improve query filtering speed.

Conclusion

Sumo Logic simplifies observability and security analytics across hybrid systems, but scalable usage depends on proper ingestion design, query tuning, and consistent field extraction. With robust diagnostics, alert monitoring, and query profiling, DevOps teams can ensure visibility and alerting fidelity across mission-critical workloads.

FAQs

1. Why are my logs not showing up in Sumo Logic?

Check sourceCategory in both collector and query. Ensure the collector is active and network/firewall allows outbound traffic.

2. How do I fix broken Field Extraction Rules?

Use Live Tail to test regexes and avoid conflicting FERs. Always test FER changes in a staging environment before deploying globally.

3. Why isn’t my scheduled alert triggering?

Ensure the query actually returns results within the scheduled window. Re-test the query manually using current timestamps.

4. What causes ingestion delays or drops?

Collectors under load, excessive regex parsing, or misconfigured log rotation can cause ingestion issues. Monitor collector health metrics.

5. How can I improve slow query performance?

Use narrower time ranges, leverage indexed fields, and avoid regex filters early in the pipeline. Use Query Performance Analyzer to inspect bottlenecks.