Skip to main content

Chariot

Chariot is Cirrus Link's MQTT broker and the primary pick for Sparkplug SCADA demos. It pairs naturally with the Cirrus Link MQTT modules on the Ignition side and ships a web console for inspecting connections and topics.

Imagecirruslink/chariot:3.0.0 (override with CHARIOT_IMAGE in .env)
Catalog kindmqtt-broker
Providesmqtt-broker
Requiresnothing
Network when split is onbackend

Preset credentials and ports​

The generated .env ships these defaults; edit them before docker compose up:

  • CHARIOT_ADMIN_PASSWORD=password: broker web admin console password.
  • CHARIOT_HTTP_PORT=8090: host port for the Chariot web UI.
  • CHARIOT_MQTT_PORT=1886: host port for the MQTT listener.

Chariot commissions itself from these on first boot.

The MQTT admin/changeme quirk​

MQTT clients authenticate as admin / changeme — a user the image auto-seeds with full ACL, independent of CHARIOT_ADMIN_PASSWORD. That env var only sets the web admin UI password; no env var changes the MQTT password. The IIoT overlay's seeded Transmission/Engine connections carry admin/changeme as an embedded JWE blob, verified live on 8.3.6 + Chariot 3.0.0.

License gate​

Chariot will not open its MQTT listener without an active license. The IIoT overlay ships a one-shot init container that REST-starts the trial on up; see Chariot trial gate.

Post-setup​

Linking a gateway is automatic when the broker is part of the IIoT overlay — the Cirrus connections are file-seeded. Adding Chariot on its own (no overlay) leaves the gateway link to you: it needs the MQTT Engine or Transmission module plus a server endpoint pointed at the broker.