Unable to send/receive message with MQTT (openHAB 2.1)

just finished installing a fresh openhabian with (openHAB 2.1) to my pi3 and I am facing a problem with sending and receiving messages from/to MQTT (mosquitto is installed on the same pi). I can see the messages arriving to the broker from different items but nothing happens in the events.log, nor if I change an item state on the UI then no message is sent to the broker (in this case event is visible in the log).
Config only shows this about mqtt initialization:
2017-12-03 15:13:18.931 [INFO ] [penhab.io.transport.mqtt.MqttService] - MQTT Service initialization completed.
2017-12-03 15:13:18.947 [INFO ] [t.mqtt.internal.MqttBrokerConnection] - Starting MQTT broker connection 'home’

URL to the MQTT broker, e.g. tcp://localhost:1883 or ssl://localhost:8883


Optional. Client id (max 23 chars) to use when connecting to the broker.

If not provided a default one is generated.


Optional. User id to authenticate with the broker.


Optional. Password to authenticate with the broker.


Thanks for your replies in advance,

i had also problems with the configuration, but fixed it with ThomDietrich here:

this could help you too, i think :wink:
good luck

Thanks for the hints, I made a mistake by not adding MQTT Binding :slight_smile: