MQTT for Meshtastic

MQTT is a lightweight messaging protocol designed for small embedded devices and low-bandwidth networks. Meshtastic utilizes your node or client's Internet connection to send and receive messages from a central server. It is often used to bridge portions of the mesh not covered by LoRa radios.

Limitations

Meshtastic packets that arrive from the MQTT server have their hop limit reduced to 0, so the receiving gateway will not rebroadcast them over LoRa. Only nodes within direct LoRa range of an MQTT-connected gateway will receive packets that come in over MQTT.

If [ALCE] Alice wants to talk to [BOB] Bob, her messages reach him over MQTT via the [MG-1] gateway. [CHAR] Charlie, however, is out of LoRa range of [MG-1] — and because packets arriving from MQTT have their hop limit reduced to 0, [MG-1] can't relay them any further. Charlie never receives Alice's messages.

Radio Configuration

Network

Your node must have working Internet access before MQTT can connect. Most users join the node to a Wi-Fi network via the Meshtastic app under Radio configuration → Network → WiFi. If your node has Ethernet, configure that instead. Confirm the Network status in the app shows a green/connected state before moving on.

MQTT

Map Reporting (Optional)

If you want your node to appear on the Portal map, enable Map reporting under the MQTT settings. The node will publish its position and basic metadata to the configured MQTT root topic on a periodic interval. Position precision is configurable — pick a value you're comfortable broadcasting publicly.

Channels

LoRa