Trying to connect to different MQTT broker than in the demo

[dawidjordaan]

1. SDK version（SDK 版本）

{

CSDTK 4.2 ($Revision: 43828 $)

SDK V2112

}

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2. In what kind of operation problems appear, and how to reproduce the problem ?（什么样的操作步骤问题会出现，是否是稳定复现，如何复现问题？）

{

I'm trying to use the MQTT to connect with AWS IOT but cannot connect to the server. No connection is established.

I am using information from this post to setup my MQTT connection settings https://github.com/Azure/azure-iot-sdk-c/issues/660

I've attached my files i'm using. mqtt_ssl_aws.zip

Getting my CA certificate from here https://docs.aws.amazon.com/iot/latest/developerguide/managing-device-certs.html

The device certificate and private keys are here: Certificate and Keys.zip

This is my tracer ouput...

Sometimes the tracer will also ouput this error after network connection like above.

}

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[Tanukaroy4494]

Try changing Qos to 1 MQTT_Publish(client,PUBLISH_TOPIC,ch,strlen(ch),1,1,0,OnPublish,NULL)

[dawidjordaan]

This problem was due to my policy linked to the certificate not allowing the connection.

The Qos should also be 0 or 1.

[farmsensor]

Hi, I also have a problem connecting to AWS: "MQTT connect to broker fail. Error: 256" With MQTT-Fx I can connect. But not with the the A9G demo script. I changed the QoS levels from 2 to 1. But it still doesn't work. What else has to be changed?

[farmsensor]

I have it running now, by making these changes: change ci.ssl_min_version = MQTT_SSL_VERSION_SSLv3; to ci.ssl_min_version = MQTT_SSL_VERSION_TLSv1_2;

delete: ci.entropy_custom = "GPRS_A9"; ci.will_qos = 2; ci.will_topic = "will"; ci.will_retain = 1; memcpy(strstr(willMsg,"GPRS")+5,imei,15); ci.will_msg = willMsg;