OH3: MQTT broker connection freezes after some time


I just updated my OH2 environment to OH3 which was so far a smooth transition.
Everything works fine but a MQTT broker connection to a Victron Cerbo device freezes after some while and linked items don’t get updates anymore (which usually come every second).

When I then edit the broker think in the GUI without changing anything the connection works again for about 2 hours.

Here’s the config of the broker connection:

The log says everything is fine:

2021-02-23 08:26:11.300 [INFO ] [.transport.mqtt.MqttBrokerConnection] - Starting MQTT broker connection to '' with clientid f6116364-3e7a-497b-a5f2-9e395760db1d
2021-02-23 08:26:11.405 [DEBUG] [ab.binding.mqtt.generic.ChannelState] - Subscribed channel mqtt:topic:3f20e560:ForwardEnergy to topic: N/d41243b50f6b/grid/30/Ac/Energy/Forward
2021-02-23 08:26:11.405 [DEBUG] [ab.binding.mqtt.generic.ChannelState] - Subscribed channel mqtt:topic:3f20e560:BatterySoC to topic: N/d41243b50f6b/battery/512/Soc
2021-02-23 08:26:11.407 [DEBUG] [ab.binding.mqtt.generic.ChannelState] - Subscribed channel mqtt:topic:3f20e560:L1Power to topic: N/d41243b50f6b/grid/30/Ac/L1/Power
2021-02-23 08:26:11.433 [INFO ] [b.core.model.script.Power_Monitoring] - Updating the daily power consumption to 3.2000000000000455 kWh
2021-02-23 08:26:11.439 [DEBUG] [ab.binding.mqtt.generic.ChannelState] - Subscribed channel mqtt:topic:3f20e560:WaterTankLevel to topic: N/d41243b50f6b/tank/20/Level
2021-02-23 08:26:11.449 [DEBUG] [ab.binding.mqtt.generic.ChannelState] - Subscribed channel mqtt:topic:3f20e560:GridLost to topic: N/d41243b50f6b/vebus/288/Alarms/GridLost

I already played around with the Reconnect time and the Heartbeat but without success.

I have a second MQTT broker thing connected to Mosquitto which seems to work all the time.

Any idea what could be the reason?

The items again were frozen, then I edited the thing without changes and then the broker connection is alive again:

2021-02-23 10:43:04.105 [INFO ] [ab.event.ThingStatusInfoChangedEvent] - Thing 'mqtt:broker:f6c7693758' changed from ONLINE to OFFLINE
2021-02-23 10:43:04.110 [INFO ] [ab.event.ThingStatusInfoChangedEvent] - Thing 'mqtt:topic:3f20e560' changed from ONLINE to OFFLINE (BRIDGE_OFFLINE)
2021-02-23 10:43:04.111 [INFO ] [ab.event.ThingStatusInfoChangedEvent] - Thing 'mqtt:topic:3f20e560' changed from OFFLINE (BRIDGE_OFFLINE) to ONLINE

It’s not an issue with the broker itself because a “mosquitto_sub -h -t “N/d41243b50f6b/#” -v” from the same machine works all the time.

You can only have one broker connection per broker. You can then use that for every topic or thing you need.

I have two different things, one is the broker connection to Mosquitto with linked items and another thing with different linked items to the Victron Cerbo.

mqtt:broker:f6c7693758 (Type=Bridge, Status=ONLINE, Label=Victron Cerbo Broker, Bridge=null)
mqtt:broker:1e46ce57b7 (Type=Bridge, Status=ONLINE, Label=MQTT Broker, Bridge=null)

Here are the items respectively:

Number VictronForwardEnergy "Netz-Verbrauch [%.1fkWh]" <plug> { channel="mqtt:topic:3f20e560:ForwardEnergy" }
Number VictronL1Power "Leistung L1 [%.1fW]" <power_watts> { channel="mqtt:topic:3f20e560:L1Power" }
Number VictronGridLost "Status [MAP(victron.map):%s]" <power_tower> { channel="mqtt:topic:3f20e560:GridLost" }
Number VictronBatterySoC "Ladestand Batterie [%.1f%%]" { channel="mqtt:topic:3f20e560:BatterySoC" }
Number VictronWaterTankLevel "Frischwassertank [%.0f%%]" <watertank_level> { channel="mqtt:topic:3f20e560:WaterTankLevel" }
Switch PortgatePing { channel="mqtt:topic:61823c9b:Ping" }
Switch PortgatePong { channel="mqtt:topic:61823c9b:Pong" }
Switch PortgateResetPong { channel="mqtt:topic:61823c9b:ResetPong" }
Switch PortgateAlive "Portgate [%s]" <pulse>
String PortgateIsAlive { channel="mqtt:topic:61823c9b:PortgateIsAlive" }

The same constellation worked well for months in OH2 but now the connection to the first broker freezes after some time.

Hope, things are clearer now.

same here, but not a Cerbo but a VenusOS on a RPI3.
I tried to work around by using a Python cript on the openhabian which connects to the external broker on the Venus and sends the received Topics to the Mosquitto on the openhabian. This wa working, but I set up openenhabian completly new and thought that would solve tghe problem. Now it’s there again.
Yesterday we set up an new openhabian OH 3.4.3 (i think), same problem. As the python script works, I think it must be a problem of the OH or the MQTT-Binding within OH