Creating an MQTT Connection Alias

An MQTT connection alias contains the configuration information that Integration Server needs to establish a connection to an MQTT server. Integration Server uses an MQTT connection alias when publishing an MQTT message. An MQTT trigger uses an MQTT connection alias to retrieve messages from the topics to which it subscribes on the MQTT server. Each Integration Server can have multiple MQTT connection aliases.

Field	Description
Connection Alias Name	Unique name for the MQTT connection alias. Each MQTT connection alias contains the configuration information needed for Integration Server to establish a connection to the MQTT server.
Description	Description for the MQTT connection alias.
Package	Name of the package that you want to associate with the MQTT connection alias. Integration Server saves the connection alias configuration in this package. When you assign an MQTT connection alias to a package, Integration Server enables and disables the alias in conjunction with the package. If you disable the package, Integration Server disables the MQTT connection alias automatically. A package retains its MQTT connection alias when the package is published to other servers. If a subscriber installs the package, the MQTT connection alias is created automatically on the subscriber's Integration Server. If you do not have a package to assign to the MQTT connection alias, leave the Package setting at WmRoot (the server's core package). This makes the MQTT connection alias available whenever Integration Server is running

Field	Description
Host	URL containing the protocol, domain, and port of the MQTT server.
Connection Client ID	Client identifier for the connections associated with this MQTT connection alias. Integration Server generates a connection client identifier automatically, but you can supply your own
Use Clean Session for Subscriptions	Whether connections created for MQTT triggers using this MQTT connection alias establish a persistent session on the MQTT server. Do one of the following: Select the Use Clean Session for Subscriptions check box to remove any previous subscriptions established by an MQTT trigger that uses this MQTT connection alias. When the session ends, the MQTT server will remove any subscriptions created by the MQTT trigger. Clear the Use Clean Session for Subscriptions check box to persist subscriptions across sessions. Any new subscriptions created by an MQTT trigger during a session will be added to the existing subscriptions for the trigger. Additionally, the subscriptions remain after the trigger disconnects. Messages sent while the trigger is disconnected will be kept if the Quality of Service (QoS) is 1 or 2. The trigger will retrieve missed messages when it reconnects.
Connection Timeout (seconds)	Maximum number of seconds that Integration Server waits for a network connection to the MQTT server to be established. A value of 0 disables the timeout, which means that Integration Server waits for a failed or successful network connection attempt. The default is 30 seconds.
Keep Alive (seconds)	The maximum number of seconds that can elapse between messages being sent to or received from the MQTT server using a connection created for this MQTT connection alias. The keep alive functionality in MQTT ensures that the connection between the MQTT client (IS) and the MQTT server is open. A value of 0 disables keep alive. The default is 60 seconds.

Field	Description
Enable Last-Will	Whether the MQTT server sends a will message on behalf of Integration Server if Integration Server disconnects abruptly from the MQTT server. A will message allows other MQTT clients to handle an abrupt disconnection. Select Enable Last-Will Message if you want the MQTT server to send a specific message to a particular topic when Integration Server disconnect abruptly from the MQTT server. Do one of the following: Select the Enable Last-Will check box to send a will message if Integration Server disconnects ungracefully. Clear the Enable Last-Will check box if Integration Server will not send a will message upon ungraceful disconnection.
Last-Will QoS	The Quality of Service for the will message. Select one of the following: At most once (0) At least once (1) Exactly once (2)
Last-Will Retained	Whether the MQTT server retains the last will message. Do one of the following: Select the Last-Will Message Retained check box to instruct the MQTT server to retain the last will message. Clear the Last-Will Message Retained check box if the MQTT server will not retain the last will message.
Last-Will Topic	The topic to which to publish the last will message. All subscribers to this topic will receive the last will message. The topic does not need to exist at the time you create the MQTT connection alias. If it does not exist the first time Integration Server uses the MQTT connection alias to establish connection, the MQTT server creates the topic.
Last-Will Message Payload	The contents of the last will message.
On Connect Message Payload	The message to send upon successful connection to the MQTT server. This is the payload of the connect message and is sent to the same topic as the Last-Will Message Topic.
On Disconnect Message Payload	The message to send upon disconnecting from the MQTT server. This is the payload of the disconnect message and is sent to the same topic as the Last-Will Message Topic.

Field	Description
User Name	User name for the Integration Server to provide for client authentication
Password	Password for the user name.