Connection Setup
The Anybus CompactCom connects automatically to an MQTT broker if the following requirements are fulfilled:
MQTT is enabled by the MQTT host object (E2h)
A valid broker URL is configured in the Network Configuration instance #50
The Anybus CompactCom is assigned a valid IP address on the network
If a connection attempt fails or an existing connection is disconnected, a new connection attempt will be performed in 10 seconds except if any of the following connection errors occur:
Erroneous broker address
Connection rejected by broker
Bad server certificate
If Secure MQTT is enabled in the Network Configuration Object, instance #57, the server identity and server certificate of the MQTT broker will be verified against the CA certificates installed in the Anybus CompactCom CA store. If the MQTT broker requests mutual authentication during the TLS handshake the device certificate enabled for MQTT will be sent to the broker. If there is no device certificate enabled for MQTT, the TLS handshake will fail. How to install device and CA certificates is described in Initial Setup and Account Configuration.