Hi, I need some pointers to help me out debug a connection issue. I got a simple setup with and ESP32 and a SimCom A7670 GSM. I am prototyping using ESP-IDF 5.1.2 and the example tcp_modem_client from the ESP-MODEM component. What I got tested/validated: MQTTconnection to HiveMQ, mosquitto AN…

@ericl Server Name Indication (SNI) verifies which hostname it’s attempting to connect to at the start of the handshaking process. For HiveMQ Cloud Serverless the hostname is added to the “Client Hello” TLS packet, you can verify it by examining the packet as illustrated in this post . I believe her…

Hello @ericl Welcome to HiveMQ Community! I’m not familiar with ESP-MODEM component but I can try to help you. To be able to connect to HiveMQ Cloud from those devices you should provide the Let’s Encrypt certificate , can you point me on how the SDK handles the TLS layer? Kind regards, Diego fro…

Hi Diego, thanks for the warm welcome. The esp-modem is only a component from espressif ( esp-protocols/components/esp_modem/README.md at master · espressif/esp-protocols · GitHub ), from which I took the modem_tcp_client example: esp-protocols/components/esp_modem/examples/modem_tcp_client at master…

Hello @ericl You’re welcome and thanks for the detailed information. HiveMQ Cloud Serverless offer requires the clients to be SNI capable when establishing the TLS connection. This is necessary to differentiate between individual tenants. Do you know if the MBED TLS implementation on this SDK supp…

Hello Diego, the yadiyadiyada is only to obfuscate my instance (dunno if its better). Your help is really appreciated. I was looking around last night and figured out the SNI feature might be the culprit. I am still new to debugging TLS connections and Iǘe got a lot to learn. I will be followin…

Diego, can you confirm I should use the string “ISRG Root X1” as the SNI common name? Cheers! dweezil@Homer:~/VSCode/modem_tcp_client/main$ openssl x509 -in isrgrootx1.pem -text Certificate: Data: Version: 3 (0x2) Serial Number: 82:10:cf:b0:d2:40:e3:59:44:63:e0:bb:…

Good morning. I’ve been studying the code and found out the current ESP-mqtt client code does not support AT transport (custom transport) in the code that activates the SNI… I’ve have to use a workaround or work directly with the modem (AT commands). Thanks a lot for your help . Cheers

Hello @ericl Were you able to complete the connection to HiveMQ through ESP32 and a A7670?

If you need some help with the AT commands, I just published a sum up of what I had to use to publish with the A7670: [image] Publishing with SIMcom A7670 Hi all Since I lost some time to understand how the module works and I wasn’t able to find resources to have a work…

ESF-IDF thru A7670 connection to free HiveMQ instance

HiveMQ Cloud

frarugi87 December 22, 2024, 10:26pm 10

If you need some help with the AT commands, I just published a sum up of what I had to use to publish with the A7670:

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ESF-IDF thru A7670 connection to free HiveMQ instance

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