Z2M devices stay unavailable after HA restart - Z2M restart required

Ben90 · October 30, 2025, 8:11am

Hello,

For some time now, when I restart Home Assistant, I have to restart Zigbee2MQTT (installed on another server) for the devices to work again in Home Assistant.

When I restart Home Assistant, I can leave it for a long time without doing anything, and the devices will still be “unavailable” even though they are functional and usable in the Zigbee2MQTT UI.
This only seems to affect Zigbee2MQTT devices and not the other MQTT devices I have.

Does anyone have any idea where this is coming from?
I haven’t seen anything in the Zigbee2MQTT logs or in Home Assistant either:

2025-10-30 08:45:01.786 INFO (MainThread) [homeassistant.setup] Setting up mqtt
2025-10-30 08:45:01.786 INFO (MainThread) [homeassistant.setup] Setup of domain mqtt took 0.00 seconds

2025-10-30 08:45:02.076 INFO (MainThread) [homeassistant.components.number] Setting up mqtt.number
2025-10-30 08:45:02.079 INFO (MainThread) [homeassistant.components.light] Setting up mqtt.light
2025-10-30 08:45:02.080 INFO (MainThread) [homeassistant.components.binary_sensor] Setting up mqtt.binary_sensor
2025-10-30 08:45:02.080 INFO (MainThread) [homeassistant.components.sensor] Setting up mqtt.sensor
2025-10-30 08:45:02.081 INFO (MainThread) [homeassistant.components.button] Setting up mqtt.button
2025-10-30 08:45:02.081 INFO (MainThread) [homeassistant.components.select] Setting up mqtt.select
2025-10-30 08:45:02.081 INFO (MainThread) [homeassistant.components.text] Setting up mqtt.text
2025-10-30 08:45:02.081 INFO (MainThread) [homeassistant.components.update] Setting up mqtt.update
2025-10-30 08:45:02.081 INFO (MainThread) [homeassistant.components.lock] Setting up mqtt.lock
2025-10-30 08:45:02.081 INFO (MainThread) [homeassistant.components.event] Setting up mqtt.event
2025-10-30 08:45:02.081 INFO (MainThread) [homeassistant.components.image] Setting up mqtt.image
2025-10-30 08:45:02.081 INFO (MainThread) [homeassistant.components.climate] Setting up mqtt.climate
2025-10-30 08:45:02.081 INFO (MainThread) [homeassistant.components.alarm_control_panel] Setting up mqtt.alarm_control_panel
2025-10-30 08:45:02.081 INFO (MainThread) [homeassistant.components.switch] Setting up mqtt.switch
2025-10-30 08:45:02.083 INFO (MainThread) [homeassistant.components.sensor] Setting up mqtt_room.sensor
2025-10-30 08:46:23.300 INFO (MainThread) [homeassistant.components.mqtt.client] 
MQTT client initialized, birth message sent

LiQuid_cOOled · October 30, 2025, 11:17am

Do you have a Mosquitto Broker installed on the separate sever?

Please share your Z2M and broker config.

walberjunior · October 30, 2025, 11:46am

I’ve also been having this problem for quite some time now.

But in my case, it only seems to happen when I do some updates to the HA Core, but I still have to investigate the OS updates.

I’m using Proxmox, HA OS in a VM, Z2M and EMQX in separate LXCs.
Nothing in the logs indicates any problem.

francisp · October 30, 2025, 12:05pm

Are these the same ?

Ben90 · October 30, 2025, 12:59pm

Yes, I had forgotten about it. It is installed on the same server as Z2M.
Here are the configurations.

Mosquitto:

listener 1883
protocol mqtt
password_file /mosquitto/config/passwd

Z2M:

version: 4
mqtt:
  base_topic: zigbee2mqtt
  server: mqtt://10.0.1.9:1883
  user: #####
  password: #####
  include_device_information: true
  keepalive: 60
  reject_unauthorized: true
  version: 4
serial:
  port: >-
    /dev/serial/by-id/usb-SMLIGHT_SMLIGHT_SLZB-MR1_4e07589a696cef11be6a99adc169b110-if00-port0
  baudrate: 115200
  adapter: ember
  rtscts: false
advanced:
  log_level: info
  channel: 20
  network_key:
    - ...
  pan_id: 42576
  ext_pan_id:
    - ...
frontend:
  enabled: true
  port: 8080
homeassistant:
  enabled: true
  experimental_event_entities: true
  discovery_topic: homeassistant
onboarding: false
devices:
    - ...

Ben90 · October 30, 2025, 1:00pm

Only during an update? Not during a manual restart?

Ben90 · October 30, 2025, 1:01pm

Yes, it seems:

fantangelo · October 30, 2025, 1:09pm

This was happening to me so I created an automation that runs when HA starts and it calls:

triggers:
  - trigger: homeassistant
    event: start
actions:
  - delay: "00:00:30"
  - action: hassio.addon_restart
    data:
      addon: 45df7312_zigbee2mqtt

This solves the problem.

francisp · October 30, 2025, 1:33pm

I won’t say that is cause, but you don’t have a persistence file configured in your mosquitto configuration.

without persistence file, HA does not receive the retained discovery messages.

walberjunior · October 30, 2025, 1:37pm

Apparently so.
If you look at the screenshot I sent, I updated around 11:20 and the z2m was disconnected for a while until I manually restarted it.
Around 23:00 I manually restarted HA and the z2m remained connected.

walberjunior · October 30, 2025, 1:49pm

Could you post your Z2M configuration?

LiQuid_cOOled · October 30, 2025, 1:58pm

You have your MR1 connected via USB?

francisp · October 30, 2025, 4:29pm

I think you need this more:

persistence true
persistence_location /var/lib/mosquitto/


include_dir /etc/mosquitto/conf.d
password_file /etc/mosquitto/passwd
listener 1883

walberjunior · October 30, 2025, 4:58pm

Unfortunately, I’m using EMQX, not Mosquitto.

Ben90 · October 31, 2025, 8:10am

I updated my configuration with persistence, I’ll see if that changes anything!

Ben90 · October 31, 2025, 8:11am

Yes, absolutely! Could that cause a problem?
I should point out that Home Assistant is running in a VM, so when it restarts, it doesn’t restart the USB ports.

LiQuid_cOOled · October 31, 2025, 8:21am

Yes that definitely could be the source of your problem. You can test the theory by changing the MR1 to Ethernet mode although that will need some tweaks to your Z2M config.

Ben90 · November 24, 2025, 9:42am

Hello, I tested it and it does indeed work, even though I don’t really understand why.

The problem is that it doesn’t suit me: I sometimes have problems with my internet connection, so I have an automation that turns off the modem plug and turns it back on after a few seconds. Except that with Zigbee2MQTT in Ethernet mode, it turns off the plug and… never turns it back on because there is no longer access to Zigbee if there is no Ethernet network.

In terms of dependency, this is a huge obstacle for me. I use Zigbee devices rather than WiFi devices to avoid this dependency…

LotF · January 30, 2026, 12:33pm

I have the same issue, but I think even when manually restarting HA.
@Ben90 have you also tried the persistence suggestion from grancisp, did this help?

@fantangelo that makes sense when Z2M is an addon, but at least I use it as a docker container and it still is running when starting up HA. Changing the start up sequenze of docker containers and implementing delays does not help either. So I don’t think this is the problem/solution for us.

Ben90 · February 7, 2026, 12:05pm

Hi, I tried all the tips here but nothing works. The solution I found is to make Home Assistant connect to my other server in SSH and make it reboot the Zigbee2MQTT container when Home Assistant restart…