In the previous post I covered the BLE → MQTT flow. Today I’m focusing on the popular Xiaomi Mi Temperature & Humidity Monitor 2 (LYWSD03MMC) and the two practical ways to integrate it with Nettemp.

Nettemp can now open up to nearby Bluetooth sensors with almost no effort. The latest nettemp_client can spin up and configure the MQTT broker, set subscriber rules, and auto-discover topics. You can then choose the hardware that listens for BLE beacons:

• ESP32 with OpenMQTTGateway (active BLE scanning, Wi‑Fi uplink)
• Raspberry Pi with Bluetooth running nettemp client + nettemp config (passive BLE sniffing)

Nettemp Client Update: MQTT, New Xiaomi Sensor, Simpler Setup

• Two-way MQTT: Nettemp Client ingests data from wireless devices (e.g., ESP running ESP Mega firmware) and forwards it to Nettemp Docker or Nettemp Cloud. It can also publish its own readings back to your broker.
• Expanded Xiaomi support: It adds the Xiaomi Mi Temperature & Humidity Monitor 2 (LYWSD03MMC). Turn the sensor on, let Nettemp detect it—no Xiaomi app needed. A Raspberry Pi Zero 2W with built-in Bluetooth works great here.
• Easier configuration: Clear options with hints in Nettemp Client Installation. Enable MQTT, pick your server, review the detected sensor, and turn on only what you need.

Welcome to NetTemp! Whether you're monitoring your home temperature, tracking server room conditions, or building a greenhouse automation system, this guide will get you started in just 10 minutes.