v2.9.0: azure_iot_hub_dps_reset() does not reset DPS registration

RE: v2.9.0: azure_iot_hub_dps_reset() does not reset DPS registration

dejans — Tue, 18 Mar 2025 10:32:43 GMT

Hi,

I have forwarded your comment internally. We will consider your suggestion.

Best regards,
Dejan

RE: v2.9.0: azure_iot_hub_dps_reset() does not reset DPS registration

Mikael Jansson — Mon, 17 Mar 2025 08:57:25 GMT

Like I said -- clarifying in the documentation exactly when you're allowed to call _dps_reset() would make things a lot easier.

RE: v2.9.0: azure_iot_hub_dps_reset() does not reset DPS registration

dejans — Fri, 14 Mar 2025 07:30:15 GMT

Hi,

Thank you for the update.

Best regards,
Dejan

RE: v2.9.0: azure_iot_hub_dps_reset() does not reset DPS registration

Mikael Jansson — Fri, 14 Mar 2025 05:58:57 GMT

I can't verify that any longer, because my problem got resolved by returning 0 at the very beginning of dps_settings_handler.

RE: v2.9.0: azure_iot_hub_dps_reset() does not reset DPS registration

dejans — Thu, 13 Mar 2025 15:34:24 GMT

Hi,

azure_iot_hub_init()

//azure_iot_hub_dps_init(); // if use_dps == false

azure_iot_hub_dps_reset()

azure_iot_hub_init()

//azure_iot_hub_dps_init(); // if use_dps == false

Did your problem get resolved when you used mentioned order?

Best regards,
Dejan

RE: v2.9.0: azure_iot_hub_dps_reset() does not reset DPS registration

Mikael Jansson — Thu, 13 Mar 2025 11:38:37 GMT

I had .use_dps = true.

Unrolling my code (based on the iothub example):

azure_iot_hub_dps_reset();

/* Using the device ID as DPS registration ID. */
int err = dps_run(&cfg.hostname, &cfg.device_id);
if (err) {
LOG_ERR("Failed to run DPS, error: %d, terminating connection attempt", err);
return -1;
}

err = azure_iot_hub_init(azure_event_handler);
if (err) {
LOG_ERR("Azure IoT Hub could not be initialized, error: %d", err);
return -2;
}

The documentation does _not_ state that azure_iot_hub_init() has to be called prior to calling azure_iot_hub_dps_reset().

Since that was not stated, I assumed it had to be called before loading the data.

So it would be a good idea to make a note in the documentation that azure_iot_hub_dps_reset() is valid in this order, and this order only:

azure_iot_hub_init() 

//azure_iot_hub_dps_init(); // if use_dps == false

azure_iot_hub_dps_reset()

azure_iot_hub_init() 

//azure_iot_hub_dps_init(); // if use_dps == false

RE: v2.9.0: azure_iot_hub_dps_reset() does not reset DPS registration

dejans — Thu, 13 Mar 2025 09:46:58 GMT

Hi,

[quote user="dejans"]

Here is what Azure DPS service says about deletion of the stored assignment information:

To delete the stored assignment information, call the azure_iot_hub_dps_reset() function. Alternatively, you can call the functions azure_iot_hub_dps_hostname_delete() or azure_iot_hub_dps_device_id_delete() to delete specific information. After calling the azure_iot_hub_dps_reset() function, the library must be initialized again. After the initialization, a new registration with the DPS can be started by calling the azure_iot_hub_dps_start() function.

Have you followed these steps but have not been able to delete stored assignment information? Have you re-initialized the library after using azure_iot_hub_dps_reset()?

[/quote]

Can you please verify that you initialized the library prior to using azure_iot_hub_dps_reset()? If you have not done that, the API is expected to fail.
The initialization of the library can be done in 2 ways:
1. If you set azure_iot_hub_config.use_dps, DPS will be initialized when azure_iot_hub_init() is called.
2. if not, you need to call azure_iot_hub_dps_init() yourself

Best regards,
Dejan

RE: v2.9.0: azure_iot_hub_dps_reset() does not reset DPS registration

dejans — Tue, 11 Mar 2025 13:14:52 GMT

Hi,

Thank you for additional information and clarification.

I will look further into this issue. I expect to get back to you by the end of the week.

Best regards,
Dejan

RE: v2.9.0: azure_iot_hub_dps_reset() does not reset DPS registration

Mikael Jansson — Mon, 10 Mar 2025 14:57:54 GMT

> To delete the stored assignment information, call the azure_iot_hub_dps_reset() function

I called this function the very first thing in main, prior to my normal code that works perfectly fine for performing DPS registration. No DPS registration was performed.

I rebooted the device. Same result.

I rebooted again, in debugger, rebooting directly after azure_iot_hub_dps_reset() was called, modified the program to remove that call, loaded into the device, started, still no DPS registration.

> Which keys are you referring to?

DPS_SETTINGS_foo in azure_iot_hub_dps_private.h

----

To clarify:

1. The device performed DPS registration and created a device in IoTHub.

2. I changed the keys on the device using nrfcredstore and updated the DPS enrollment thingy on Azure.

3. When I started again, DPS was not performed.

I'm suspecting that because that DPS was performed previously, and even though I did run the reset function, the setings table got into an undefined state that caused DPS to never run.

The workaround I did was to make sure the DPS code thought it had loaded empty keys, forcing it to run DPS registration, specifically so "dps_reg_ctx.status = AZURE_IOT_HUB_DPS_REG_STATUS_ASSIGNED;" was never called.

As to why, I'm just speculating. I followed the instructions by calling the reset function first thing, and the code didn't do what it said it should do. I'd say that's a bug.

RE: v2.9.0: azure_iot_hub_dps_reset() does not reset DPS registration

dejans — Mon, 10 Mar 2025 14:12:11 GMT

Hi,

[quote user=""]

According to the documentation, you should run azure_iot_hub_dps_reset() in order to force DPS registration again.

But if the device has previously been enrolled and a device created using DPS, and then the keys changed on the device, the reset function doesn't remove the required keys to trigger DPS.

[/quote]

Which keys are you referring to? Can you elaborate on these steps?

Here is what Azure DPS service says about deletion of the stored assignment information:

Have you followed these steps but have not been able to delete stored assignment information? Have you re-initialized the library after using azure_iot_hub_dps_reset()?

Best regards,
Dejan