MKR1000 mqtt example failed, error code -2

[farellsujanto]

Hi, I've tried the example provided in this library, it connects well to my wifi but I cant seem to connect to the broker (I've tried google iot core and aws iot core, but none also works and return the same error). It always returns error code -2.

Board version: Arduino SAMD Boards 1.8.6
Firmware: WINC1501 Model B (19.6.1)

[realonedoe]

Hi

I've the same issue:

Hardware:
Nano 33 IOT
Nina Firmware 1.3.0

Software:
ArduinoMqttClient 0.1.4
WiFiNina 1.5.0

1. Take example "ArduinoMqttClient - WiFi Simple Sender"

2. Use it with test.mosquitto.org Broker over port 1883
   2.1 All is running fine

3. Try it with SSL/TLS
   3.1 Change port from 1883 to 8883
   3.2 Change WifiClient to WifiSSLClient
   3.3 Update SSL root certificate (add mosquitto.org:443)
   3.3.1 I did try with test.mosquitto.org:8883 too!

The MQTT-Client returns Error -2, that means (Connection refused by server).

Thanks.

[aentinger]

Hi 👋 can you please provide a minimal code which demonstrates the problematic behaviour?

[realonedoe]

HI

Here is the Example-Code with changed objects for TLS-Connection to test.mosquitto.org:8883

Zip-File containes

• Code without SECRETS-File for WLAN!
• Picture "Upload certificate" over FirmwareUpdater
• Picture with Error and opened MQTTClient.h for Error-Message

Thanks.

Greetz and happy easter.
Ben

Nano33IOT_MQTT_TLS.zip

[aentinger]

Hi. I spoke with @Rocketct who took a look at your code and he suggests to take a look at https://github.com/arduino/ArduinoCloudProviderExamples which contains examples when one wants to use TLS/SSL with MQTT.

[realonedoe]

Hi,
thanks for clearify. Unfortunalety in our case it does not solve the problem, because my company has a own mosquitto-server and we don't wan't use any providers.

Anyway, thank you for your help, I appreciate it.

[aentinger]

Hi @realonedoe 👋
If you are so inclined you might try this:

• Upload your certificate into the Crypto Chip following the procedure described here.
• Base your application on this example code.
• Disable Server-Name-Identification (see here for further information)

-BearSSLClient sslClient(wifiClient);
+BearSSLClient sslClient(wifiClient, true);

[aentinger]

Good morning @realonedoe 👋 I'm closing this now, if you need anything else please just reopen this issue.