PDUs, cooling units, UPS systems and rack sensors report power, temperature and humidity across every hall and site. Edge gateways publish those values once over MQTT, and your DCIM, NOC alerting and energy reporting each subscribe to what they need.
No card required
You build the DCIM views, alerts and reports, ConnectMQ moves the data. Edge gateways in each hall read PDUs, cooling units, UPS systems and rack sensors and publish on change; your DCIM, capacity planning, NOC alerting and energy reporting each subscribe in parallel. Your BMS stays in control of the equipment.
dc/dfw1/hall-b/rack-b14/env
dc/dfw1/hall-b/rack-b14/pdu-a/power
dc/dfw1/hall-b/crac-02/state (retained)The usual set-up is a collector at each site that polls every PDU, cooling unit and UPS over SNMP or Modbus, every minute or so, whether anything changed or not. With ConnectMQ, an edge gateway in each hall still reads the equipment locally but publishes only when a value changes — and every system that needs it subscribes.
A common data center MQTT setup: an edge gateway in the hall publishes rack temperatures on change, the DCIM in the NOC subscribes, and the site’s BMS gateway listens for cooling setpoints. Hall and NOC both connect out to ConnectMQ over TLS; the BMS stays in charge of the cooling units.
03:14 Edge gateway in hall B
Reads the rack sensors on the local network and publishes only when a value changes: rack B-14’s inlet air has reached 31.2 °C.
dc/dfw1/hall-b/rack-b14/env → {"inlet":31.2,"rh":38}03:14 DCIM in the NOC
Subscribed to every hall through ConnectMQ. Its rule for inlets above 27 °C opens incident INC-2291 and requests an 18 °C supply-air setpoint on CRAC-02.
dc/dfw1/hall-b/crac-02/set → {"supply":18}03:15 BMS gateway → CRAC-02
The only client allowed to write to hall B’s cooling: it applies the setpoint over BACnet, CRAC-02 raises its fan to 85 % and the gateway publishes the new state.
dc/dfw1/hall-b/crac-02/state → {"supply":18,"fan":85}03:21 On-call engineer
Gets the NOC notification with the values. A few minutes later rack B-14 is back at 26.4 °C, and the incident shows every step.
When a new NOC screen connects, it subscribes to dc/dfw1/hall-b/+/env and gets every rack’s last reading at once — the edge gateway publishes every reading with the retain flag, so nothing waits for the next change.
Machines, PLC gateways, OEE and quality data
Hubs, sensors and Home Assistant setups
Vehicle tracking, telematics and cold chain
Meters, EV chargers, solar and batteries
Smart devices you ship to your own customers
Robot fleets talking to fleet managers and AI pipelines
Streetlights, parking, air and waste sensors
Soil probes, weather stations and irrigation
From first ESP32 to classroom labs
Start on the Free plan with no card. Basic covers up to 100 concurrent connections — enough for the edge and BMS gateways of a few halls and the systems that subscribe to them. Move to Scale when you add sites.
