As a DIY enthusiast, I was aware that maintaining a smart home requires time and attention to detail. I use a lot of affordable smart devices that operate over the Zigbee protocol with Home Assistant. Most of my IoT and smart devices utilize the MQTT protocol, also known as Message Queuing Telemetry Transport, to communicate with each other over a network. I chose it since MQTT is lightweight, ideal for low-power devices, and efficient for enabling smart devices to communicate in real-time.

Most off-the-shelf smart devices don't support MQTT natively unless they are flashed with custom firmware or used with a compatible bridge. I use a couple of Philips Hue smart bulbs, linked to a Zigbee2MQTT bridge, which connects to an MQTT broker in Home Assistant. When they stop working, I troubleshoot them with a free, open-source app called MQTT Explorer. As the name suggests, it works only with smart home devices that work over the MQTT protocol. The MQTT Explorer is a game-changer diagnostic tool for my smart home. I often use it with Home Assistant to pinpoint the reason behind a malfunctioning smart home device.

Why did I pick MQTT Explorer to troubleshoot smart home devices?

Best for low-power, DIY-style devices

While using Home Assistant, I initially used the Logbook and System Logs to troubleshoot the devices, but it didn't help much. The Home Assistant community recommended the MQTT Explorer to help me diagnose and manage my smart and IoT devices that use MQTT.

That's how I investigate which of my smart bulbs becomes inactive after a specific event, such as a power outage. With this app, it's easier to check the device's state or test out features. Using this app, I discovered that my Home Assistant automations break because my family keeps switching the smart devices off after a power outage.

Even while setting up smart bulbs, sending MQTT messages (payloads) to test or control their color, state, and brightness helped further customize and perfect the automation. The diagnostic tool is a lifesaver in revealing the goof-ups in improper configuration and automation failures. I used the tool with several devices that the Zigbee2MQTT frontend can't connect to.

Finding and fixing troublesome smart home devices

Sifting through the topics and messages

Unlike Home Assistant's manageable UI and YAML configurations, MQTT Explorer requires some learning. Once I entered the login credentials for my MQTT server, it instantly presented a nested tree of everything happening through an MQTT broker server. For instance, I see Zigbee2MQTT and Home Assistant topics, as well as top-level string labels for different components. The former lists it as a bridge for smart devices, while the latter displays the different topic trees for sensors, switches, lights, buttons, and other devices. That helps me narrow down the search and look for non-responsive devices. I look forward to the search bar at the top when I have hundreds of IoT devices and sensors in my home.

Under the Lights topic, my Philips Hue smart bulbs appear with a 64-bit MAC address along with the messages, configuration, their state, and logs. Clicking on any bulb's config reveals the associated data in JSON format in a separate column. I can further review its message history and even publish (push) a custom message to other devices through it. Of course, that requires me to format the message values in JSON or XML format to make it easier for MQTT brokers to process.

Teaming up with Node-RED and Home Assistant for troubleshooting

Combining multiple tools for diagnosing

Sometimes, it's not just one smart device acting up. I often nosedive into the Home Assistant's Logs when I can't get enough information from MQTT Explorer about a failed integration. That's how I learned that the PulseAudio service kept crashing and consuming system resources.

While MQTT Explorer helps with monitoring and managing smart devices, handling the automations with Node-RED integration becomes easy in Home Assistant. Additionally, it offers an enhanced interface for handling errors and debugging automation flows, particularly those that integrate with external systems outside Home Assistant. I struggle with its steep learning curve. That said, Node-RED can help you troubleshoot the exact point where the automation breaks and soup up complicated ones.

For Z-Wave smart devices, the Z-Wave JS UI add-on for Home Assistant is a great addition. Meanwhile, the ESPHome Device Builder add-on serves as a dashboard for configuring and monitoring multiple ESPHome devices and sensors. TasmoAdmin add-on helps to troubleshoot smart devices flashed with Tasmota firmware. Using it alongside MQTT Explorer enables the configuration and checking of smart device status.

Ultimate tool for the DIY smart home enthusiasts

MQTT Explorer has quickly become a must-have diagnostic tool for DIY enthusiasts like me, as I continue to discover new ways to make the best of Home Assistant. Several times, it revealed why select sensors and smart devices had become unresponsive. This feature-rich tool is capable of setting up alerts about the state of smart home devices and works on Windows, macOS, and Linux. It has become my go-to tool for examining and removing outdated messages from smart devices I no longer use with Home Assistant. With MQTT Explorer in your diagnostic arsenal, you can confidently add smart devices and sensors to improve your smart home.