Zigbee2MQTT Health Check: Find Broken and Stale Zigbee Devices
A Zigbee network normally fails one boring device at a time: a battery dies, a sensor disappears or a weak route finally gives up. Zigbee2MQTT gives you the information needed to spot those problems before somebody tells you the lights have stopped working again.
Turn on availability
In Zigbee2MQTT settings, enable availability. Powered routers and battery devices behave differently, so Zigbee2MQTT uses different active/passive timeouts before marking them unavailable.
Use the device list
Show useful columns such as device type, LQI, last seen, availability and battery. LQI is a clue rather than a verdict: a low number is worth investigating when it stays poor or coincides with actual reliability problems.
Look at the network map
Load the Zigbee2MQTT network map to see the coordinator, routers, end devices and the routes between them. This is particularly useful when thick walls or poor router placement leave part of the house with a weak mesh.
Remove genuinely lost devices carefully
If a device is gone for good, Zigbee2MQTT can force-remove it. Do not block it from joining again unless you genuinely never want that device back, because you may simply find it in a drawer next week.
Expose Last Seen and Link Quality to Home Assistant
Enable the relevant MQTT entities in Home Assistant. Doing this in bulk from the Entities screen is much faster than opening every device individually.
Build a health dashboard
A Home Assistant Markdown card can list stale/broken and working Zigbee devices. Template helpers can count each group, giving you a simple red/green health indicator.
Turn the count into an alert
Once the stale-device count exists as a helper, an automation can notify you when it rises above a sensible threshold. That turns Zigbee maintenance from waiting for complaints into something you can spot proactively.
Do not forget the physical network
Software cannot repeal physics. Put powered Zigbee routers where they can actually bridge difficult areas, and remember that thick walls and radio interference matter.