nRF9160DK: MQTT Connection Error - Azure IoT Hub

[Sam]

Hi, 

I have been using the nRF9160-DK sample code to connect my dk to my hosted Azure IoT Hub. I have followed the documentation for creating the certificates for both the CA Cert to put on my IoT Hub and as well the client-side certificate. I used the AT Client to turn off the modem before updating the certificates as told to do so in the documentation and as well testing the certificates using the sample verification and data from that simulation was able to send. However, when trying to do so from the device failed. I am not sure whether this is a certificate issue or a code issue. Please advise. I am not using DPS fyi

I have been troubleshooting for a couple of days now and I can't seem to understand where this issue is coming from. Below is the logging information for what is happening to my device. 

Thanks in advance! 

/resized-image/__size/640x480/__key/communityserver-discussions-components-files/4/Logging.jpg_2D00_640x480.jpg. 

*** Booting Zephyr OS build v3.2.99-ncs2 ***
[00:00:00.531,005] <inf> azure_iot_hub_sample: Azure IoT Hub sample started
[00:00:00.531,127] <inf> azure_iot_hub_sample: Connecting to LTE network
+CEREG: 2,"3BC5","03090216",7
+CSCON: 1
[00:00:16.855,957] <inf> azure_iot_hub_sample: LTE cell changed: Cell ID: 50922006, Tracking area: 15301
[00:00:17.616,760] <inf> azure_iot_hub_sample: RRC mode: Connected
+CEREG: 5,"3BC5","03090216",7,,,"00001010","11000001"
[00:00:20.076,843] <inf> azure_iot_hub_sample: Network registration status: Connected - roaming
[00:00:20.076,995] <inf> azure_iot_hub_sample: Connected to LTE network
[00:00:20.077,056] <dbg> azure_iot_hub: iot_hub_state_set: State transition: STATE_UNINIT --> STATE_DISCONNECTED
[00:00:20.077,056] <inf> azure_iot_hub_sample: Azure IoT Hub library initialized
[00:00:20.077,117] <dbg> azure_iot_hub: iot_hub_state_set: State transition: STATE_DISCONNECTED --> STATE_CONNECTING
[00:00:20.077,148] <inf> azure_iot_hub_sample: AZURE_IOT_HUB_EVT_CONNECTING
[00:00:20.077,239] <dbg> azure_iot_hub: azure_iot_hub_connect: User name: HubIoTSZGP.azure-devices.net/iotdemodevice/?api-version=2020-09-30&DeviceClientType=azsdk-c%2F1.4.0-beta.2
[00:00:20.077,270] <dbg> azure_iot_hub: azure_iot_hub_connect: User name buffer size is 128, actual user name size is: 106
[00:00:20.078,521] <inf> azure_iot_hub_sample: PSM parameter update: TAU: 1152000, Active time: 20
[00:00:20.577,545] <err> mqtt_helper: mqtt_connect, error: -111
[00:00:20.577,545] <err> azure_iot_hub: mqtt_helper_connect failed, error: -111
[00:00:20.577,606] <dbg> azure_iot_hub: iot_hub_state_set: State transition: STATE_CONNECTING --> STATE_DISCONNECTED
[00:00:20.577,636] <err> azure_iot_hub_sample: azure_iot_hub_connect failed: -111
+CSCON: 0
[00:00:27.182,922] <inf> azure_iot_hub_sample: RRC mode: Idle

[Sam]

**Update It seems like I have fixed the certificate issue. I am now getting this in my logs however and I still don't see the data in my Azure IoT Hub. 

*** Booting Zephyr OS build v3.2.99-ncs2 ***
[00:00:00.522,186] <inf> azure_iot_hub_sample: Azure IoT Hub sample started
[00:00:00.522,308] <inf> azure_iot_hub_sample: Connecting to LTE network
+CEREG: 2,"3BEB","01610D04",7
+CSCON: 1
+CEREG: 2,"3BEB","01610D04",7,0,11
[00:00:20.043,518] <inf> azure_iot_hub_sample: LTE cell changed: Cell ID: 23137540, Tracking area: 15339
[00:00:20.311,553] <inf> azure_iot_hub_sample: RRC mode: Connected
+CSCON: 0
+CEREG: 2,"874A","0B78580F",7
[00:00:21.653,564] <inf> azure_iot_hub_sample: RRC mode: Idle
[00:00:22.121,490] <inf> azure_iot_hub_sample: LTE cell changed: Cell ID: 192436239, Tracking area: 34634
+CSCON: 1
+CEREG: 2,"874A","0B78580F",7,0,11
[00:00:22.696,289] <inf> azure_iot_hub_sample: RRC mode: Connected
+CSCON: 0
+CEREG: 2,"874A","0B78580F",7
+CSCON: 1
[00:00:24.092,559] <inf> azure_iot_hub_sample: RRC mode: Idle
[00:00:24.284,332] <inf> azure_iot_hub_sample: RRC mode: Connected
+CEREG: 5,"874A","0B78580F",7,,,"00001010","11000001"
[00:00:28.785,552] <inf> azure_iot_hub_sample: Network registration status: Connected - roaming
[00:00:28.785,736] <inf> azure_iot_hub_sample: Connected to LTE network
[00:00:28.785,766] <dbg> azure_iot_hub: iot_hub_state_set: State transition: STATE_UNINIT --> STATE_DISCONNECTED
[00:00:28.785,797] <inf> azure_iot_hub_sample: Azure IoT Hub library initialized
[00:00:28.785,858] <dbg> azure_iot_hub: iot_hub_state_set: State transition: STATE_DISCONNECTED --> STATE_CONNECTING
[00:00:28.785,858] <inf> azure_iot_hub_sample: AZURE_IOT_HUB_EVT_CONNECTING
[00:00:28.786,071] <dbg> azure_iot_hub: azure_iot_hub_connect: User name: HubIoTSZGP.azure-devices.net/iotdemodevice/?api-version=2020-09-30&DeviceClientType=azsdk-c%2F1.4.0-beta.2
[00:00:28.786,071] <dbg> azure_iot_hub: azure_iot_hub_connect: User name buffer size is 128, actual user name size is: 106
[00:00:28.787,170] <inf> azure_iot_hub_sample: PSM parameter update: TAU: 1152000, Active time: 20
[00:00:32.657,501] <inf> azure_iot_hub_sample: Connection request sent to IoT Hub
[00:00:32.897,613] <dbg> azure_iot_hub: iot_hub_state_set: State transition: STATE_CONNECTING --> STATE_CONNECTED
[00:00:32.897,613] <dbg> azure_iot_hub: on_connack: MQTT mqtt_client connected
[00:00:32.898,712] <dbg> azure_iot_hub: topic_subscribe: Successfully subscribed to default topics
[00:00:32.898,712] <inf> azure_iot_hub_sample: AZURE_IOT_HUB_EVT_CONNECTED
[00:00:33.050,872] <inf> azure_iot_hub_sample: AZURE_IOT_HUB_EVT_READY
[00:00:33.050,994] <dbg> azure_iot_hub: request_id_create_and_get: Request ID not specified, using "330"
[00:00:33.051,269] <inf> azure_iot_hub_sample: Sending event:{"temperature":25.1,"timestamp":33051}
[00:00:33.051,757] <dbg> azure_iot_hub: device_twin_request: Device twin requested
[00:00:33.052,307] <inf> azure_iot_hub_sample: Event was successfully sent
[00:00:33.052,337] <inf> azure_iot_hub_sample: Next event will be sent in 20 seconds
[00:00:33.187,774] <wrn> azure_iot_hub: DISCONNECT, result: -128
[00:00:33.187,835] <dbg> azure_iot_hub: iot_hub_state_set: State transition: STATE_CONNECTED --> STATE_DISCONNECTED
[00:00:33.187,866] <inf> azure_iot_hub_sample: AZURE_IOT_HUB_EVT_DISCONNECTED
[00:00:33.187,896] <err> mqtt_helper: Cloud MQTT input error: -128
+CSCON: 0
[00:00:38.900,634] <inf> azure_iot_hub_sample: RRC mode: Idle

[Sam]

***Another update. I fixed the whole thing... Data is finally being sent and I can see the data and send commands from IoT Hub to turn off or on the LED. 

[Reimer]

Hey Sam,

I am currently experiencing the same problem you encountered.

Therefore I am curious to know how you solved your error: -128. Cant seem to get beyond this issue so it would be a huge help if you could share some information as to how you have resolved the issue.

Kind regards

Reimer    

[Sam]

Hey Reimer, 

Apologies for the late reply, just saw your message. 

To be frank with you, this was 6 months ago roughly but if I remember correctly this error was specific to a certificate issue. I had to flash the device with the certificate that nRF provides. 

It seemed like I had the wrong certificate on the hardware which led to this error -128. Here is the documentation I followed: nRF9160: Azure FOTA — nRF Connect SDK 2.2.0 documentation (nordicsemi.com)

Try flashing the Baltimore certificate to the device and see if that fixes the issue. That is how I did it at least and after that it started working. 

"

If TLS is used as the transport layer, you must provision the required certificates to the device. The certificates that need to be provisioned depends on the location of the hosted FOTA image, and the TLS settings that are configured at the endpoint from where the file is downloaded. If, for instance, Azure Blob Storage is used for hosting, you can use the same root certificate (Baltimore CyberTrust Root certificate) that is used in the Azure IoT Hub connection. See Prerequisites for connecting to Azure IoT Hub for more information.

If a host other than Azure is used, the certificate requirements might be different. See the documentation for the respective host to locate the correct certificates. You can provision the certificates using the same procedure as described in Provisioning of the certificates."

Here is the link to the baltimore certificate download from azure: Azure Certificate Authority details | Microsoft Learn

[Reimer]

Hey Sam,

Thank you for taking the time to respond. Haven't been able to solve it in the meantime so it is greatly appreciated.

I have currently configured the sample to match the deviceID and IDScope with my iot hub and enabled DPS. Used the same security tag 10 and 11, where i have with Baltimore Root ca 10 and Digicert global Root Ca 2 with 11 both as CA certificate. Both have the same Client certificate which at the moment is the Device ca and have previously attempted with combining the client- and intermediate CA. The Private key is the device's private key also for both security tags.

I feel like I should have the correct certificates but it just continues to show the error -128

Sam said:

I had to flash the device with the certificate that nRF provides.

What exactly does this involve? I have made my own RootCa, IntermediateCa, DeviceCa and private keys, do you know if they are unusable?

Are you aware of a specific security tag or something that is preferred or should be avoided.

I am using DPS but it doesn't seem to be a problem to establish that connection.

I'll leave my terminal output, I have tried looking at the Serial terminal instead of LTE Link Monitor which returns some more information.

*** Booting Zephyr OS build v3.3.99-ncs1-1 ***
[00:00:00.508,880] <inf> nrf_modem_lib_trace: Trace thread ready
[00:00:00.510,498] <inf> nrf_modem_lib_trace: Trace level override: 2
[00:00:00.510,528] <inf> azure_iot_hub_sample: Azure IoT Hub sample started
[00:00:00.510,559] <inf> azure_iot_hub_sample: Device ID: testdevice-01
[00:00:00.510,650] <inf> azure_iot_hub_sample: Connecting to LTE network
+CEREG: 2,"36DA","0285B720",7
+CSCON: 1
[00:00:01.550,140] <inf> azure_iot_hub_sample: LTE cell changed: Cell ID: 42317600, Tracking area: 14042
[00:00:01.615,692] <inf> azure_iot_hub_sample: RRC mode: Connected
+CEREG: 5,"36DA","0285B720",7,,,"11100000","11100000"
[00:00:03.170,013] <inf> azure_iot_hub_sample: Network registration status: Connected - roaming
[00:00:03.170,166] <inf> azure_iot_hub_sample: Connected to LTE network
[00:00:03.170,196] <inf> azure_iot_hub_sample: Starting DPS
[00:00:03.170,227] <dbg> azure_iot_hub_dps: dps_reg_id_set: Setting DPS registration ID: testdevice-01
[00:00:03.170,288] <dbg> azure_iot_hub_dps: dps_id_scope_set: No ID scope provided, using ID scope from Kconfig: 0ne00AFEE24
[00:00:03.170,349] <dbg> azure_iot_hub_dps: dps_id_scope_set: Setting DPS ID scope: 0ne00AFEE24
[00:00:03.170,623] <dbg> azure_iot_hub_dps: dps_on_settings_loaded: Settings fully loaded
[00:00:03.170,684] <dbg> azure_iot_hub_dps: dps_state_set: State transition: DPS_STATE_UNINIT --> DPS_STATE_DISCONNECTED
[00:00:03.170,684] <inf> azure_iot_hub_sample: DPS registration status: AZURE_IOT_HUB_DPS_REG_STATUS_NOT_STARTED
[00:00:03.170,745] <dbg> azure_iot_hub_dps: provisioning_client_init: Client ID (size: 13): testdevice-01
[00:00:03.170,928] <inf> azure_iot_hub_sample: PSM parameter update: TAU: 3240, Active time: -1
[00:00:03.171,051] <dbg> azure_iot_hub_dps: provisioning_client_init: User name (size: 62): 0ne00AFEE24/registrations/testdevice-01/api-version=2019-03-31
[00:00:16.021,057] <dbg> azure_iot_hub_dps: dps_state_set: State transition: DPS_STATE_DISCONNECTED --> DPS_STATE_CONNECTING
[00:00:16.021,118] <dbg> azure_iot_hub_dps: timeout_work_restart_timer: Restarting timeout: 90 sec
[00:00:16.021,118] <inf> azure_iot_hub_sample: The DPS process has started, timeout is set to 90 seconds
[00:00:16.113,708] <dbg> azure_iot_hub_dps: dps_state_set: State transition: DPS_STATE_CONNECTING --> DPS_STATE_CONNECTED
[00:00:16.113,708] <dbg> azure_iot_hub_dps: on_connack: MQTT connected
[00:00:16.113,769] <dbg> azure_iot_hub_dps: topic_subscribe: Subscribing to: $dps/registrations/res/#
[00:00:16.114,715] <dbg> azure_iot_hub_dps: topic_subscribe: Successfully subscribed to DPS topics
[00:00:16.114,746] <dbg> azure_iot_hub_dps: timeout_work_restart_timer: Restarting timeout: 90 sec
[00:00:16.275,543] <dbg> azure_iot_hub_dps: dps_send_reg_request: Topic buffer size is 224, actual topic size is: 46
[00:00:16.275,604] <dbg> azure_iot_hub_dps: dps_send_reg_request: Publishing to DPS registration topic: $dps/registrations/PUT/iotdps-register/?$rid=1, no payload
[00:00:16.276,367] <inf> azure_iot_hub_sample: DPS registration status: AZURE_IOT_HUB_DPS_REG_STATUS_ASSIGNING
[00:00:16.276,397] <dbg> azure_iot_hub_dps: timeout_work_restart_timer: Restarting timeout: 90 sec
[00:00:16.421,478] <dbg> azure_iot_hub_dps: timeout_work_restart_timer: Restarting timeout: 90 sec
[00:00:16.600,219] <dbg> azure_iot_hub_dps: timeout_work_restart_timer: Restarting timeout: 90 sec
[00:00:16.600,372] <dbg> azure_iot_hub_dps: handle_reg_update: DPS registration request response received
[00:00:16.600,372] <dbg> azure_iot_hub_dps: handle_reg_update: Status code is 202
[00:00:16.600,402] <dbg> azure_iot_hub_dps: handle_reg_update: Received retry value: 3
[00:00:16.600,433] <dbg> azure_iot_hub_dps: handle_reg_update: Operation ID: 5.4fd4ce520c89aa14.6f403c5b-55bd-4a17-9bdf-a0f3026468f9
[00:00:16.600,463] <inf> azure_iot_hub_sample: DPS registration status: AZURE_IOT_HUB_DPS_REG_STATUS_ASSIGNING
[00:00:19.761,901] <dbg> azure_iot_hub: iot_hub_state_set: State transition: STATE_DISCONNECTED --> STATE_CONNECTING
--- 18 messages dropped ---
[00:00:19.761,932] <inf> azure_iot_hub_sample: AZURE_IOT_HUB_EVT_CONNECTING
[00:00:19.761,932] <dbg> azure_iot_hub: azure_iot_hub_connect: Starting DPS, timeout is 90 seconds
[00:00:19.761,993] <dbg> azure_iot_hub_dps: dps_reg_id_set: Setting DPS registration ID: testdevice-01
[00:00:19.762,023] <dbg> azure_iot_hub_dps: dps_id_scope_set: Setting DPS ID scope: 0ne00AFEE24
[00:00:19.762,451] <dbg> azure_iot_hub_dps: dps_settings_handler: Azure IoT Hub hostname length found: 27
[00:00:19.762,847] <dbg> azure_iot_hub_dps: dps_settings_handler: Azure IoT Hub hostname found: SensOrigo.azure-devices.net
[00:00:19.763,122] <dbg> azure_iot_hub_dps: dps_settings_handler: Assigned device ID length found: 13
[00:00:19.763,336] <dbg> azure_iot_hub_dps: dps_settings_handler: Assigned device ID found: testdevice-01
[00:00:19.763,427] <dbg> azure_iot_hub_dps: dps_on_settings_loaded: Settings fully loaded
[00:00:19.763,458] <dbg> azure_iot_hub: dps_handler: AZURE_IOT_HUB_DPS_REG_STATUS_NOT_STARTED
[00:00:19.763,519] <dbg> azure_iot_hub_dps: azure_iot_hub_dps_start: Device "testdevice-01" is assigned to IoT hub: SensOrigo.azure-devices.net
[00:00:19.763,549] <dbg> azure_iot_hub_dps: azure_iot_hub_dps_start: To re-register, call azure_iot_hub_dps_reset() first
[00:00:19.763,549] <dbg> azure_iot_hub: azure_iot_hub_connect: Already assigned to an IoT hub, skipping DPS
[00:00:19.763,610] <dbg> azure_iot_hub_dps: azure_iot_hub_dps_hostname_get: hostname_ptr: 0x200125bf, hostname_len: 27
[00:00:19.763,641] <dbg> azure_iot_hub: azure_iot_hub_connect: Using the assigned hub (size: 27): SensOrigo.azure-devices.net
[00:00:19.763,671] <dbg> azure_iot_hub_dps: azure_iot_hub_dps_device_id_get: dev_id_ptr: 0x2001253f, dev_id_len: 13
[00:00:19.763,732] <dbg> azure_iot_hub: azure_iot_hub_connect: Using the assigned device ID: testdevice-01
[00:00:19.763,824] <dbg> azure_iot_hub: azure_iot_hub_connect: User name: SensOrigo.azure-devices.net/testdevice-01/?api-version=2020-09-30&DeviceClientType=azsdk-c%2F1.4.0-beta.2
[00:00:19.763,854] <dbg> azure_iot_hub: azure_iot_hub_connect: User name buffer size is 160, actual user name size is: 105
[00:00:31.811,279] <inf> azure_iot_hub_sample: Connection request sent to IoT Hub
[00:00:32.017,333] <dbg> azure_iot_hub: iot_hub_state_set: State transition: STATE_CONNECTING --> STATE_CONNECTED
[00:00:32.017,333] <dbg> azure_iot_hub: on_connack: MQTT mqtt_client connected
[00:00:32.018,463] <dbg> azure_iot_hub: topic_subscribe: Successfully subscribed to default topics
[00:00:32.018,463] <inf> azure_iot_hub_sample: AZURE_IOT_HUB_EVT_CONNECTED
[00:00:32.106,628] <inf> azure_iot_hub_sample: AZURE_IOT_HUB_EVT_READY
[00:00:32.106,842] <inf> azure_iot_hub_sample: Sending event:{"temperature":25.6,"timestamp":32106}
[00:00:32.107,055] <dbg> azure_iot_hub: request_id_create_and_get: Request ID not specified, using "321"
[00:00:32.108,123] <inf> azure_iot_hub_sample: Event was successfully sent
[00:00:32.108,123] <inf> azure_iot_hub_sample: Next event will be sent in 60 seconds
[00:00:32.109,344] <dbg> azure_iot_hub: device_twin_request: Device twin requested
[00:00:32.635,070] <wrn> azure_iot_hub: DISCONNECT, result: -128
[00:00:32.635,131] <dbg> azure_iot_hub: iot_hub_state_set: State transition: STATE_CONNECTED --> STATE_DISCONNECTED
[00:00:32.635,162] <inf> azure_iot_hub_sample: AZURE_IOT_HUB_EVT_DISCONNECTED
[00:00:32.635,162] <err> mqtt_helper: Cloud MQTT input error: -128
+CSCON: 0
[00:00:39.001,556] <inf> azure_iot_hub_sample: RRC mode: Idle
[00:01:32.108,306] <inf> azure_iot_hub_sample: Sending event:{"temperature":25.8,"timestamp":92108}
[00:01:32.108,367] <wrn> azure_iot_hub: Azure IoT Hub is not connected
[00:01:32.108,367] <err> azure_iot_hub_sample: Failed to send event
[00:01:32.108,367] <inf> azure_iot_hub_sample: Next event will be sent in 60 seconds

Kind regards,

Reimer