NATS Connection Exhaustion: Maximum Connections Exceeded

Detects high-severity NATS server failures when the configured maximum connection limit is exceeded, preventing new clients from establishing connections. This represents a critical messaging infrastructure failure that can cause cascading outages across distributed systems relying on NATS for inter-service communication and real-time data streaming.

This rule helps identify problems such as:

• NATS server max_connections setting too low for current workload demands
• Auto-scaling events creating simultaneous connection burst attempts that overwhelm the server
• Connection pool misconfigurations in client applications creating excessive connections
• Service restarts causing mass reconnection attempts within short time windows
• Connection leaks from applications not properly closing NATS connections after use
• Kubernetes pod restarts causing simultaneous reconnection storms during deployments
• Load testing or traffic spikes overwhelming NATS connection limits and blocking legitimate traffic

Reproduction: Docker-based setup with NATS server (3-connection limit) and 6 client containers to reliably trigger connection exhaustion scenarios.

/claim #77
/close #77

Reproducible test setup (Maintainers invited) : nats connection

Live CRE Link : CRE playground