NRF9160 aws_iot sample: mqtt topic add does not work

[danielboe]

Hi,

I use the latest connect sdk 1.4.0 and modem firmware 1.2.2. If I load the default aws_iot code it does not subscribe to the topics set in "topics_list" in the code. However the device is somehow still subscriped to a topic I set with an older firmware with mqtt_simple example and still gets messages. This behaviour does not chance even after reset and completely erease of the device. 

So my quess is the topic subscription is set in the modem part and does not get reset with the aws_iot sample. What could be the issue?

Best regards

[Hakon]

Hello,

Have you tried deleting the device shadow as described here?

[danielboe]

Why this shoukd help? I subscribe to a custom mqtt topic. Can you explain what is the connection to the device shadow? 

[Hakon]

I was thinking the device shadow could contain some old metadata about the device. Anyway, MQTT information is handled in the application, the modem has nothing to do with it, so I'm thinking this could be an AWS issue. Have you tried contacting the AWS support team?

[danielboe]

I deleted the device shadow and also recreated the device on aws-iot with no changes. I still get the updates to the shadow from the device. I also get messages from device to aws via MQTT topic. Also the FOTA update triggers and works.

Whats not working is to simple send data to a aws topic to the device (which I subscribed there) Strange, because I think the FOTA also sends some kind of info on some topic to the device

[danielboe]

I tried it again with different samples on a new device and its the same. if I flash the aws_iot sample it connects, updates shadow and can send mqtt but not receive on subscribed topic. If I then flash my old mqtt sample it subscibes to the topic set in there and can receive. If I then flash again the aws_iot sample with completely different topic subscriptions it still can´t receive on them but gets messages from the topic set in the old mqtt firmware.

Again, this topic is not set in the aws_iot firmware! So somehow it gets saved on a space in the device and survives firmware update and power loss for minutes! And the subscription in the aws_iot firmware never works!