sample LWM2M client fails to bootstrap in Leshan and Coiote

RE: sample LWM2M client fails to bootstrap in Leshan and Coiote

RicardoCarvalho — Mon, 09 Oct 2023 17:11:38 GMT

Hi Øyvind,

I apologize for this late reply, I have been on vacation these last few days.

I just want to say that the solution of removing the credentials stored in the modem worked, I can now bootstrap both the Leshan server and the Coiote server.

Two questions:
- Leshan's <sec_tag> is always 35724861 and Coiote's is 35724862?
- Does the AT command AT%XFACTORYRESET=0 not clear these credentials?

Thanks a lot for the help!

Regards,

Ricardo

RE: sample LWM2M client fails to bootstrap in Leshan and Coiote

Achim Kraus — Tue, 19 Sep 2023 14:18:24 GMT

In the meantime I was able to test also the leshan bootstrap.

Build:

west build -b nrf9160dk_nrf9160_ns --pristine -- -DOVERLAY_CONFIG="overlay-leshan-bootstrap.conf" -DCONFIG_NRF_MODEM_LIB_TRACE=y

Flash:

west flash --erase

(Please use --erase. Not that the "silence" after

"*** Booting Zephyr OS build v3.3.99-ncs1-1 ***"

is caused by a mangling firmware update in slot 2.)

Then you need to configure your device in:

- bootstrap server: leshan.eclipseprojects.io/.../

- data server: https://leshan.eclipseprojects.io

And with the "Cellular Monitor" you will be able the see the trace and ip-capture.

devzone.nordicsemi.com/.../trace_2D00_2023_2D00_09_2D00_19T14_2D00_08_2D00_44.687Z.zip

RE: sample LWM2M client fails to bootstrap in Leshan and Coiote

Øyvind — Tue, 19 Sep 2023 08:25:01 GMT

Sorry for the late reply. Have been waiting for an answer from our experts.

The bootstrap process might fail as it will not overwrite the credentials in the modem. You will need to ensure that you have removed the credentials from the sec_tags, as described under Provisioning the identity and security credentials. You can use the AT client sample to ensure that they have been removed with the %CMNG AT command, for example:

AT%CMNG=3,35724861,3
AT%CMNG=3,35724861,4
AT%CMNG=3,35724862,3
AT%CMNG=3,35724862,4

If you have done this correctly, the bootstrap process should work.

You must also ensure that you have written the security information to both Leshan bootstrap server and the Leshan server.

Leshan security entry:

Leshan bootstrap entries:

The images might not be in the correct order. Please review and let me know if anything is unclear.

As Achim Kraus points out, a modem trace will be best in order to see what fails in the process. [quote user="Hannibalhz"]But the software is stop run, the log only prints the following characters.[/quote]Hannibalhz have you added other configurations to your LwM2M client? The AT Host library exposes the AT command interface of the cellular modem for supported devices on an external serial interface. This is not needed in order to capture modem traces but will allow e.g. Cellular Monitor to issue commands to your device in order to collect relevant information from the SIM, network, etc.

Kind regards,
Øyvind

RE: sample LWM2M client fails to bootstrap in Leshan and Coiote

Achim Kraus — Tue, 19 Sep 2023 08:22:59 GMT

I tried to get capture using NCS 2.4.2, mfw 1.3.5, DK v1.1.0

I enabled the modem trace with "CONFIG_NRF_MODEM_LIB_TRACE=y". On "my machine" that works.

Wiresharks shows, that the PSK handshake works with Californium, there is no extra 0 in the identity nor an issue in the secret (sometime hex and plain is mixed up).

Not sure, what goes wrong in your case.

RE: sample LWM2M client fails to bootstrap in Leshan and Coiote

Achim Kraus — Tue, 19 Sep 2023 06:23:09 GMT

I'm not common to the Nordic LwM2M client implementation.Just from the error description it sounds like a DTLS handshake issue. For PSK that's mostly a mismatching secret, here I guess it may also be a mismatch in the identity.

> stop run

AFAIK, only CONFIG_NRF_MODEM_LIB_TRACE=y is required, CONFIG_AT_HOST_LIBRARY=y isn't. Maybe someone from Nordic can guide you how to enable the modem trace on a DK 0.9 with the LwM2M client.

The only idea left without trace would be to try the "blind shot" and test with removing the "+1", if didn't have done that already.

RE: sample LWM2M client fails to bootstrap in Leshan and Coiote

Hannibalhz — Mon, 18 Sep 2023 02:28:17 GMT

Hi Achim

I tried to add the following configure to LWM2M sample.

CONFIG_NRF_MODEM_LIB_TRACE=y
CONFIG_AT_HOST_LIBRARY=y

But the software is stop run, the log only prints the following characters.

*** Booting Zephyr OS build v3.3.99-ncs1-1 ***

Could you give me some good suggestions?

Best regards,

Hannibal Wang

RE: sample LWM2M client fails to bootstrap in Leshan and Coiote

Achim Kraus — Thu, 14 Sep 2023 10:38:14 GMT

Do you know how to provide a modem trace from the communication with the bootstrap server?

If so, you may check with wireshark, if the device repeats its "CLIENT_KEY_EXCHANGE" message 2 or 3 times without an response from the server. If that's the case, I would analyze the client's PSK identity sent in that "CLIENT_KEY_EXCHANGE". Not sure, but the source code (lwm2m_security.c, line 659) smells for adding the trailing 0, which I guess is not intended by the servers. But I may also be wrong.

lwm2m_security.c, line 659:

return lwm2m_security_set(sec_obj_inst, SEC_MODE_PSK, psk_id, strlen(psk_id) + 1, NULL, 0,
psk, psk_len);

Edited:

Just in the case, a modem trace is not possible, you may also try a "blind shot"; remove the "+ 1" from the "strlen(psk_id) + 1" and see, if that already helps. If not, then it's hard to say more without the modem trace.

RE: sample LWM2M client fails to bootstrap in Leshan and Coiote

Hannibalhz — Thu, 14 Sep 2023 08:25:53 GMT

Hi Øyvind

I used NBIOT of China Mobile. I encounter the same problem.

devzone.nordicsemi.com/.../7002.log.txt

So could you give our some good suggestions?
Best regards,

Hannibal

RE: sample LWM2M client fails to bootstrap in Leshan and Coiote

RicardoCarvalho — Tue, 12 Sep 2023 14:27:03 GMT

Hi Øyvind,

Yes, I followed the steps indicated in the server setup, both for Leshan and Coiote.

I'm using the PSK from the example.

Setup on Leshan Bootstrap:

setup on Coyote Bootstrap:

I am using a Truphone SIM card with LTE-M connection

[00:00:04.693,542] <inf> app_lwm2m_client: Connected to LTE network

Here is the information collected from the modem:

[00:00:14.050,964] <dbg> app_lwm2m_client: main: Modem Device - APP name: lwm2m_client
[00:00:14.051,025] <dbg> app_lwm2m_client: main: Modem Device - APP version: v2.4.2
[00:00:14.051,055] <dbg> app_lwm2m_client: main: Modem Device - Board: nrf9160dk_nrf9160
[00:00:14.051,055] <dbg> app_lwm2m_client: main: Modem Device - Batery: 5242
[00:00:14.051,116] <dbg> app_lwm2m_client: main: Modem SIM - ICCID: 8944477100001296139
[00:00:14.051,177] <dbg> app_lwm2m_client: main: Modem SIM - IMSI: 208090063100493
[00:00:14.051,177] <dbg> app_lwm2m_client: main: Modem SIM - UICC: 0
[00:00:14.051,239] <dbg> app_lwm2m_client: main: Modem Network - APN: iot.truphone.com
[00:00:14.051,269] <dbg> app_lwm2m_client: main: Modem Network - Area Code: 000B
[00:00:14.051,300] <dbg> app_lwm2m_client: main: Modem Network - Cell ID: 136021005.000000
[00:00:14.051,330] <dbg> app_lwm2m_client: main: Modem Network - Cell ID hex: 081B840D
[00:00:14.051,361] <dbg> app_lwm2m_client: main: Modem Network - LTE Band: 20
[00:00:14.051,391] <dbg> app_lwm2m_client: main: Modem Network - Operator: 26801
[00:00:14.051,422] <dbg> app_lwm2m_client: main: Modem Network - Time and Date: 0
[00:00:14.051,422] <dbg> app_lwm2m_client: main: Modem Network - GPS suport Mode: 1
[00:00:14.051,483] <dbg> app_lwm2m_client: main: Modem Network - IP: 10.138.127.177
[00:00:14.051,483] <dbg> app_lwm2m_client: main: Modem Network - LTE-M Mode: 1
[00:00:14.051,544] <dbg> app_lwm2m_client: main: Modem Network - Mobile Country Code: 268
[00:00:14.051,574] <dbg> app_lwm2m_client: main: Modem Network - NB-IoT Mode: 0
[00:00:14.051,574] <dbg> app_lwm2m_client: main: Modem Network - Current Mode: 2
[00:00:14.051,605] <dbg> app_lwm2m_client: main: Modem Network - RSRP: 59
[00:00:14.051,666] <dbg> app_lwm2m_client: main: Modem Network - Supported LTE Bands: (1,2,3,4,5,8,12,13,18,19,20,25,26,28,66)
[00:00:14.051,696] <dbg> app_lwm2m_client: main: Modem Network - Current Mode: 2

Thank you for your help.

Regards,

Ricardo

RE: sample LWM2M client fails to bootstrap in Leshan and Coiote

Øyvind — Tue, 12 Sep 2023 09:16:55 GMT

Hello Ricardo,

To verify, have you added the device to e.g. Coiote as described under Server setup? Is the PSK correctly configured?

-116 indicates a time-out. Is this LTE-M or NB-IoT? What network and SIM are you using? Will forward to our LwM2M experts for more insight.

Kind regards,
Øyvind