Back to All ScenariosPASSEDqueue / connection_storm Apache Kafka 3.7 Connection Storm — SYN Flood or Client Bug on Debian 12 Bookworm
Apache Kafka 3.7 is receiving thousands of new connections per second, overwhelming the accept queue. Legitimate connections being dropped.
Pattern
CONNECTION_REFUSED
| Metric | Expected | Actual | Result |
|---|
| Pattern Recognition | CONNECTION_REFUSED | CONNECTION_REFUSED | |
| Severity Assessment | HIGH | CRITICAL | |
| Incident Correlation | N/A | None | |
| Cascade Escalation | N/A | No | |
| Remediation | — | Auto-Heal — Corax resolves autonomously | |
Scenario Conditions
Debian 12 Bookworm. Apache Kafka 3.7 seeing 5876 new connections/sec (normal: 52). SYN backlog full. accept queue overflowing. net.core.somaxconn=205.
Injected Error Messages (1)
Apache Kafka 3.7 on Debian 12 Bookworm — connection refused for legitimate clients, 5876 new conns/sec (normal: 52), SYN backlog full, accept queue overflow, ECONNREFUSED
Neural Engine Root Cause Analysis
Connection refused — service is likely crashed or not listening on the expected port.
Remediation Plan
Restart the target service. If recurring, check for memory leaks or crash loops.
Improvements Applied
- Severity: CRITICAL (expected HIGH)
Tested: 2026-04-02Monitors: 1 | Incidents: 1Test ID: cmnhnqz5p08fulig7z6tnp71p