If this is the wrong section I apologize, but I’m not sure where to categorize it.
Lately in the past week and a half, my Home Assistant will stall once or twice in an evening, usually between 9:30 PM CST and 10:15 PM CST. I’ve been reviewing logs but I can’t find anything relevant or why.
My HA instance is a VM running on vmWare Workstation, on a Windows Server 2019 Essentials. been deployed for several years without issue. It has both Zigbee and Z-Wave USB dongles, attached via extension cables, and ported into the VM. That is the only external hardware connected.
I don’t know if it’s a recent Core update (two have been applied within the past month) or something else, but the system will jam. I’m unable to access the interface via mobile or PC Web Browser. It seems to stall, and after awhile it acts like it’s done a reboot or refreshed entirely.
It also happens when I’m not trying to access it. I have a Zigbee sensor on my Garage Door, and it alerts via Notification when the door is closed. I got two alerts last night it was closed in the space of 40 minutes, because the Zigbee integration reloaded.
What logs should I be looking for? I’ve already checked the physical host server. No disk errors, Event logs are clean, no scheduled tasks occurring that would impact the VM during the timeframe. Other services that run on the same physical host are fine and not impacted.
I don’t suppose there are any suggestions? This did not happen evening of Wednesday, but did happen again Thursday evening. Around 10:10 PM or so, same symptom. Was watching TV and got an alert that my garage door was closed, quick check and it looks like everything cycled again.
This morning I managed to catch this in the logs. However, searching I find similar errors from about two years ago. I’ve not touched my Zigbee network in awhile, no new devices paired to it.
Logger: asyncio
Source: runner.py:289
First occurred: July 30, 2026 at 9:52:49 PM (4 occurrences)
Last logged: July 30, 2026 at 9:52:49 PM
socket.send() raised exception.
Logger: zigpy.application
Source: /usr/local/lib/python3.14/site-packages/zigpy/application.py:943
First occurred: July 30, 2026 at 10:12:23 PM (1 occurrence)
Last logged: July 30, 2026 at 10:12:23 PM
Watchdog failure
Traceback (most recent call last):
File “/usr/local/lib/python3.14/site-packages/zigpy/application.py”, line 941, in _watchdog_loop
await self.watchdog_feed()
File “/usr/local/lib/python3.14/site-packages/zigpy/application.py”, line 927, in watchdog_feed
await self._watchdog_feed()
File “/usr/local/lib/python3.14/site-packages/bellows/zigbee/application.py”, line 1168, in _watchdog_feed
current_counters = await self._ezsp.read_counters()
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File “/usr/local/lib/python3.14/site-packages/bellows/ezsp/v4/init.py”, line 191, in read_counters
(res,) = await self.readCounters()
^^^^^^^^^^^^^^^^^^^^^^^^^
File “/usr/local/lib/python3.14/site-packages/bellows/ezsp/protocol.py”, line 124, in command
await self._gw.send_data(data)
File “/usr/local/lib/python3.14/site-packages/bellows/uart.py”, line 26, in send_data
await self._transport.send_data(data)
File “/usr/local/lib/python3.14/site-packages/bellows/ash.py”, line 735, in send_data
await asyncio.shield(
…<6 lines>…
)
File “/usr/local/lib/python3.14/site-packages/bellows/ash.py”, line 660, in _send_data_frame
raise NcpFailure(
t.NcpResetCode.ERROR_EXCEEDED_MAXIMUM_ACK_TIMEOUT_COUNT
)
bellows.ash.NcpFailure: NcpResetCode.ERROR_EXCEEDED_MAXIMUM_ACK_TIMEOUT_COUNT
Your watchdog triggered because your ZigBee network timed out?
Is your network load affected by external factors such as neighborhood internet traffic, peaking mid evening? Are you watching TV via internet, and was via an aerial before?
Are you experiencing interference to your ZigBee devices?
The Home Assistant VM runs on a physical host that also runs Jellyfin media server. Yes it’s usually streaming one or two streams in the evening, but this setup has been working this way for several years.
I’m not aware of interference on my ZigBee network. The Zigbee band is specifically on a different channel to not interfere with my internal wireless network.
Only TV that we use it internally from Jellyfin. I upgraded my internet four months ago to Fiber. Again this has only been an issue the past couple weeks.
Yesterday I applied the HA O/S update, and last night this happened five to six times, so it was more than previous nights. I’m seriously wondering if it’s something with a recent Core update
- Installation method Home Assistant OS
- Core 2026.7.4
- Supervisor 2026.07.5
- Operating System 18.2
This has still been occurring nightly. However, this AM I just upgraded to Core 2026.8.0 so we’ll see if it happens again tonight.
It still happened, just before 10 PM CST. So this Core update didn’t resolve it.