Zigbee Network Crash

I’ve not seen this issue before, but my entire zigbee network at home crashed today. Not a single device was responsive.

Restarting home assistant fixed the issue, but I’ve never seen this issue before. The start of the logs are as follows:-

2024-08-28 14:34:38.691 WARNING (MainThread) [bellows.zigbee.application] NWK conflict is reported for 0xd787
2024-08-28 14:34:38.692 WARNING (MainThread) [bellows.zigbee.application] Found 70:b3:d5:2b:60:03:3d:fc device for 0xd787 NWK conflict: _TZ3000_okaz9tjs TS011F
2024-08-28 14:34:40.147 ERROR (MainThread) [homeassistant] Error doing job: Task exception was never retrieved (None)
Traceback (most recent call last):
  File "/usr/local/lib/python3.12/site-packages/zha/zigbee/cluster_handlers/__init__.py", line 66, in wrap_zigpy_exceptions
    yield
  File "/usr/local/lib/python3.12/site-packages/zha/zigbee/cluster_handlers/__init__.py", line 84, in wrapper
    return await RETRYABLE_REQUEST_DECORATOR(func)(*args, **kwargs)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/local/lib/python3.12/site-packages/zigpy/util.py", line 136, in retry
    return await func()
           ^^^^^^^^^^^^
  File "/usr/local/lib/python3.12/site-packages/zigpy/zcl/__init__.py", line 377, in request
    return await self._endpoint.request(
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/local/lib/python3.12/site-packages/zigpy/endpoint.py", line 265, in request
    return await self.device.request(
           ^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/local/lib/python3.12/site-packages/zigpy/device.py", line 339, in request
    await send_request()
  File "/usr/local/lib/python3.12/site-packages/zigpy/application.py", line 833, in request
    await self.send_packet(
  File "/usr/local/lib/python3.12/site-packages/bellows/zigbee/application.py", line 793, in send_packet
    raise zigpy.exceptions.DeliveryError(
zigpy.exceptions.DeliveryError: Failed to enqueue message: <sl_Status.NETWORK_DOWN: 22>

The above exception was the direct cause of the following exception:

Traceback (most recent call last):
  File "/usr/local/lib/python3.12/site-packages/zha/application/gateway.py", line 605, in async_device_initialized
    await self._async_device_rejoined(zha_device)
  File "/usr/local/lib/python3.12/site-packages/zha/application/gateway.py", line 646, in _async_device_rejoined
    await zha_device.async_configure()
  File "/usr/local/lib/python3.12/site-packages/zha/zigbee/device.py", line 745, in async_configure
    await self.identify_ch.trigger_effect(
  File "/usr/local/lib/python3.12/site-packages/zha/zigbee/cluster_handlers/__init__.py", line 83, in wrapper
    with wrap_zigpy_exceptions():
  File "/usr/local/lib/python3.12/contextlib.py", line 158, in __exit__
    self.gen.throw(value)
  File "/usr/local/lib/python3.12/site-packages/zha/zigbee/cluster_handlers/__init__.py", line 75, in wrap_zigpy_exceptions
    raise ZHAException(message) from exc
zha.exceptions.ZHAException: Failed to send request: Failed to enqueue message: <sl_Status.NETWORK_DOWN: 22>
2024-08-28 15:08:28.189 WARNING (MainThread) [zigpy.backups] Failed to create a network backup
Traceback (most recent call last):
  File "/usr/local/lib/python3.12/site-packages/zigpy/backups.py", line 220, in _backup_loop
    await self.create_backup()
  File "/usr/local/lib/python3.12/site-packages/zigpy/backups.py", line 143, in create_backup
    await self.app.load_network_info(load_devices=load_devices)
  File "/usr/local/lib/python3.12/site-packages/bellows/zigbee/application.py", line 240, in load_network_info
    await self._ensure_network_running()
  File "/usr/local/lib/python3.12/site-packages/bellows/zigbee/application.py", line 174, in _ensure_network_running
    raise NetworkNotFormed("Node is not part of a network")
zigpy.exceptions.NetworkNotFormed: Node is not part of a network

Any thoughts on what might have caused this ?

Hi, have a look at this extensive guide for troubleshooting zigbee: Zigbee networks: how to guide for avoiding interference + optimize using Zigbee Router devices (repeaters/extenders) to get a stable mesh network with best possible range and coverage

@Nick4 - thanks for the link, I’ve used that before and the network has been stable for years. First time I’ve ever seen this. I guess I’ll just have to keep an eye out and see if it happens again.