Connecting to Private MQTT broker

[yeo]

Dear Nordic Team, 

I am currently using nrf9160 for MQTT transmission. I have successfully connected to a public MQTT broker which is HiveMQ and transmitted data to HiveMQ. The next step I am trying to achieve is to transfer data to a private MQTT broker which will require a username and password. May I know how I configure these parameters in the prj.conf file? The image below is my configuration for HiveMQ. 

[Øyvind]

Hello, 

You will need to know if the MQTT broker uses TLS for private connection. If so, you can build your project using nrf\samples\nrf9160\mqtt_simple\overlay-tls.conf.

If you are using the simple_mqtt sample, you can add the user_name and password in client_init(). From zephyr\include\zephyr\net\mqtt.h

	/** User name (if any) to be used for the connection. NULL indicates
	 *  no user name.
	 */
	struct mqtt_utf8 *user_name;

	/** Password (if any) to be used for the connection. Note that if
	 *  password is provided, user name shall also be provided. NULL
	 *  indicates no password.
	 */
	struct mqtt_utf8 *password;

More information can be found in the MQTT library documentation

Kind regards,
Øyvind.

[yeo]

Hi, sorry for the late reply. I have modified my code in client_init(), prj.conf, and Kconfig. However, I still couldn't send the data data to private MQTT broker. I have attached the code below. 8741.MQTT_simple.zip

[yeo]

8816.mqtt_simple_sensor (2).zipHi, Please refer to this file instead

[yeo]

Hi, is there anyone to answer my question?

[Øyvind]

Hello, 

Looking at the last project that you have attached, there is no username or password added to client_init().

Both are configured to NULL.

Have a look at the sample zephyr\samples\net\cloud\mqtt_azure. I.e. this shows how to configure the username and password. The sample uses KConfig to define the Kconfig symbols which you can add value to in prj.conf. In client_init() the following is added:

//add to top off client_init()
static struct mqtt_utf8 password;
static struct mqtt_utf8 username;


client->client_id.utf8 = (uint8_t *)MQTT_CLIENTID;
client->client_id.size = strlen(MQTT_CLIENTID);

password.utf8 = (uint8_t *)CONFIG_SAMPLE_CLOUD_AZURE_PASSWORD;
password.size = strlen(CONFIG_SAMPLE_CLOUD_AZURE_PASSWORD);

client->password = &password;

username.utf8 = (uint8_t *)CONFIG_SAMPLE_CLOUD_AZURE_USERNAME;
username.size = strlen(CONFIG_SAMPLE_CLOUD_AZURE_USERNAME);

client->user_name = &username;

This can be used as an example to get your project up and running.

[yeo]

MQTT_simple (3).zip

This is my modified code. However, it still doesn't send messages to the private MQTT broker. Can you please help me to have a look?

best regards,

Yeo Rhi Khin

[Øyvind]

Do you have any log output to share as well? Do you receive any errors?  Difficult to tell what is failing.

[Øyvind]

The sample works

[yeo]

But if the mqtt broker receives the message it will show that messages are received. There are no messages received output in the terminal. 

Best regards, 

Yeo Rhi Khin

[Øyvind]

What happens on the broker side? Does this receive the published message?