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Version: 2.11

Server Monitoring

Server monitoring endpoints provide detailed information about the NATS server state, performance metrics, and operational health.

Overview​

NATS Server exposes HTTP monitoring endpoints that return JSON-formatted data about server operations. These endpoints are essential for:

  • Health checks and liveness probes
  • Performance monitoring
  • Troubleshooting issues
  • Capacity planning
  • Integration with monitoring systems

Available Endpoints​

Varz​

General server information including:

  • Server version and configuration
  • Current connections and subscriptions
  • Message rates and data throughput
  • Memory and CPU usage
  • Cluster membership information

Connz​

Detailed connection information for all clients connected to the server:

  • Client connection details
  • Connection state and statistics
  • IP addresses and ports
  • Subscription counts per connection

Subsz​

Subscription routing details:

  • Active subscriptions
  • Queue group information
  • Subscription statistics
  • Filtering and pagination options

Routez​

Cluster route information:

  • Route connections between cluster nodes
  • Route statistics and health
  • Cluster topology information

Gatewayz​

Gateway connections for superclusters:

  • Gateway connection status
  • Remote gateway information
  • Traffic statistics between gateways

Leafz​

Leafnode connections:

  • Leafnode server connections
  • Remote leafnode details
  • Connection statistics

Accountz​

Account information:

  • Account configuration and limits
  • Connection and subscription counts per account
  • Import/export configurations

Accstatz​

Account statistics:

  • Detailed account usage statistics
  • Message and byte counts
  • Connection metrics per account

JSz​

JetStream information:

  • Stream and consumer details
  • JetStream cluster status
  • Memory and storage usage

Healthz​

Health check endpoint:

  • Server health status
  • Suitable for liveness/readiness probes
  • Simple OK/Error responses

Statsz​

Server statistics summary:

  • Aggregated server metrics
  • Performance statistics
  • System resource usage

IPQueuesz​

IP queue information:

  • Client IP-based queue statistics
  • Connection queuing metrics

Idz​

Server identification:

  • Server identity information
  • Unique server identifiers

Profilez​

Server profiling data:

  • CPU and memory profiling endpoints
  • Performance debugging information

Raftz​

Raft consensus information:

  • JetStream Raft cluster details
  • Leader election status
  • Raft log information

Access Configuration​

Monitoring endpoints are configured in the server configuration file:

http_port: 8222

Endpoints are then accessible at:

http://localhost:8222/varz

Security Considerations​

  • Use authentication to protect monitoring endpoints
  • Consider TLS for encrypted monitoring traffic
  • Limit access to monitoring endpoints via firewall rules
  • Be aware that some endpoints may expose sensitive information

Integration​

Monitoring endpoints integrate well with:

  • Prometheus for metrics collection
  • Grafana for visualization
  • Kubernetes liveness/readiness probes
  • Custom monitoring solutions
  • Alert managers