Server Configuration

Last Updated: 2026-07-29

server controls network listeners and telemetry endpoints. Example:

server:
  tcp:
    v3:
      addr: ":1883"
      protocol: "v3"
    v5:
      addr: ":1884"
      protocol: "v5"
  websocket:
    plain:
      addr: ":8083"
      path: "/mqtt"
      protocol: "auto" # auto | v3 | v5
  http:
    plain:
      addr: ":8080"
  amqp:
    plain:
      addr: ":5672"
  amqp091:
    plain:
      addr: ":5682"
    local:
      addr: ":5683"
      max_connections: 32
      cert_file: "/run/secrets/fluxmq_server_cert"
      key_file: "/run/secrets/fluxmq_server_key"
      ca_file: "/run/secrets/local_client_ca"
      client_auth: "require"

  health_enabled: true
  health_addr: ":8081"

  metrics_enabled: false
  metrics_addr: "localhost:4317"

  otel_metrics_enabled: true
  otel_traces_enabled: false
  otel_trace_sample_rate: 0.1

  admin_api_addr: ":8082"

Key Fields

• Listener families: tcp, websocket, http, coap, amqp, amqp091.
• amqp091.local is a private mTLS listener reserved for auth.local_principals; it never uses external auth or blocking hooks and requires a positive max_connections cap. It carries service-to-service traffic from a fixed set of statically configured internal producers, such as audit or event streams — not general client, device, or tenant connections.
• Listener addresses: addr (empty disables the specific listener).
• MQTT parser mode per listener: TCP v3/v5 listeners are protocol-pinned; WebSocket listeners can use protocol (auto, v3, v5).
• Listener limits/timeouts: max_connections, read_timeout, write_timeout.
• WebSocket specifics: path, allowed_origins.
• Health/observability: health_enabled, health_addr, metrics_enabled, metrics_addr.
• OpenTelemetry identity/tuning: otel_service_name, otel_service_version, otel_metrics_enabled, otel_traces_enabled, otel_trace_sample_rate.
• Admin API server: admin_api_addr (empty string disables the admin API listener).
• Graceful shutdown: shutdown_timeout.

Learn More

• Configuration reference