LWM2M registration timeout

[arun-kmr]

Describe the bug
The lwm2m example throws LWM2M registration timeout . The device seems to connect to the leshan server as i can see that on web interface of leshan-demo-server (which is running on http://localhost:8080 ). the client last update changes in every 30-45 second with new registration id.
uart log:
[00:04:52.172,454] net_lwm2m_rd_client: RD Client started with endpoint 'nrf52840_pca10056' and client lifetime 30
[00:04:52.682,037] net_lwm2m_rd_client.sm_send_registration: Non dtls
[00:04:52.682,067] net_lwm2m_rd_client.sm_send_registration: registration sent [fdde:ad00:beef:0:3696:3458:e373:be67]
[00:04:55.036,499] net_lwm2m_engine.retransmit_request: Resending message: 0x20001750
[00:04:59.726,745] net_lwm2m_engine.retransmit_request: Resending message: 0x20001750
[00:05:09.097,259] net_lwm2m_engine.retransmit_request: Resending message: 0x20001750
[00:05:27.828,308] net_lwm2m_rd_client: Registration Timeout
[00:05:27.828,308] net_lwm2m_client_app.rd_client_event: Disconnected
[00:05:27.828,308] net_lwm2m_client_app.rd_client_event: Registration failure!

To Reproduce
Steps to reproduce the behavior:

1. cd sample/net/lwm2m

2. mkdir build && cd build

3. cmake -GNinja -DBOARD=nrf52840_pca10056 -DOVERLAY_CONFIG=overlay-ot.conf ..
   overlay-ot.conf.txt

4. ninja

Expected behavior
It should successfully connected to the leshan server

Screenshots or console output

Environment (please complete the following information):

• OS: Linux
• Toolchain: Zephyr-sdk
• Commit id : 06d7835

[mike-scott]

Oddly, I don't see overlay-ot.conf here: https://github.com/zephyrproject-rtos/zephyr/tree/master/samples/net/lwm2m_client

I was going to add one, once #12343 is merged and communication via OT border router confirmed.

But right now, I don't think this is an issue?

[arun-kmr]

I am using overlay-ot.conf defined in echo_client example. I think it is serving it's purpose. please take a look if i am missing something in that file. and of course i will check that PR #12343

[nashif]

@mike-scott what is the status here?

[mike-scott]

I need to merge an OpenThread overlay.conf that I've tested before this can be fixed. It's not so much of a "bug" as an untested feature atm.

[mike-scott]

@nashif Do I have the ability to get an OpenThread overlay for LwM2M into 1.14 now that the freeze is active?

[mike-scott]

Removed bug tag and replaced with feature

[arun-kmr]

got it working after pr merger.

[nduongn]

Hi @ARN-SOFT, Can you help to share your overlay-ot.conf file for lwm2m. I test with the overlay-ot.conf.txt you shared in the first post but it can not run. Thanks.

[mike-scott]

@andynnd Can you open a new issue asking for an overlay-ot.conf to be added to the LwM2M sample? I have one and will get to it when I'm back from ELC.

[nduongn]

@mike-scott I just open a new issue at #18601. Thanks.