Cumulocity IoT Tips and Tricks - Using MQTTLens as client for Cumulocity

If you have problems connecting MQTTLens as client to Cumulocity, try using a shorter client ID. MQTTLens uses MQTT version 3.1 but incorrectly ignores the limit on client ID lengths in MQTT 3.1. 

Alternatively, try changing to another MQTT client such as MQTTBox.