Join an existing mesh Network with a mesh provisioner (nrf mesh sdk)

[neicureuil]

Hi,

Is it possible to join an existing mesh network with a provisioner made on Nrf52840 (s140)  ?

I have used the provisioner example to make a provisioner which actually create a new mesh network. But after an "erase all" of the board, the provisioning data are lost and the board can't reconnect to the network because information are lost during the erase (logic).

Is there a way to extract the provisioning data and mesh network data from the board to use them later on an other board ?

My goal is to create a mesh network with a device, then store in a file all the information related to this network to be able later with another board to join this network and add new devices.

I have setup a serial connection to send data through the usb port to my computer so I could retrieve and return the data by this method.

I know that this is possible in the mobile application with the "export network" and "import network" functions but I can't reproduce the functionality with the mesh SDK.

Is this possible? If yes how?
Regards

Used sdk :

- nRF5_SDK_16.0.0_98a08e2

- nrf5_SDK_for_Mesh_v4.2.0_src

Board used :

- nrf52840 evaluation board

- nrf52832 evaluation board

[Hung Bui]

Hi Neicureuil, 

The easiest way of "exporting" the provisioner data to another board is to just do a hex dump of the flash content of the board (nrfjprog --readcode ). You can then use this hex file to flash on other board to access the network. 
However doing that doesn't allow to have multiple provisioner at the same time and every time you provision a new node you would need to do a new hex dump. And that you would have only one firmware for all the provisioner. 

A more advanced option is to only copy the specific data that need to be restored on a new board so that you can customized it to export and import. What you need to copy is : network key, application keys, device keys, the composition data of nodes.
We don't have the code of doing that. You would need to study the code and send such data back to PC.

I would suggest to go for option 1 if you don't need any extra requirement. If you don't want to clone the whole flash, you can think of only copy the flash area that the dsm store the database. This way you can customize the firmware, and only copy the database flash area. 

[neicureuil]

Hi,

Thank for your response.

Is there a way to copy the flash area without using "nrfjprog" because at the end, the goal is to put the code on a nrf52840 usb dongle which will be connected to a linux autonomous computer (maybe directly from the code).

[Hung Bui]

Hi, 
Then I think you need to study the code and see how the data is restored (read from flash) on every boot (in functino mesh_config_load() ).

After that you can just read the data and send it to the Linux computer via UART/USB.  And on the new provisioner you can try to replace the mesh_config_load() with a function that you made with the data fed from the computer. 

[neicureuil]

Hi,

I have successfully reload the 3 key (app, dev and net) and I'am now able to receive command's callbacks and device alive event from provisioned devices after a node reset.

But I can't configure my device using the config model because the "dsm_address_handle_get" function return an "NRF_ERROR_NOT_FOUND".

I think its because acutally I didn't reload the composition data of nodes. I looked at the code to try to extract and re-import the datas but I didn't understand how its works.

Can you give me some advice to do that or is there a way to configure a device without these addresses (because the other models always work without) or is there a way to ask the devices for this information in order to reload them in memory ?

Regards

[Hung Bui]

Hei Neucureuil, 
Have you added the addresses of the devices (the provisioned nodes) in to the dsm database ? You would need to call dsm_address_publish_add() to add the address(es), after that the call dsm_address_handle_get() should work .

[neicureuil]

Hi,

No I haven't add the address to the dsm database because after a reset I don't know this address.

This address is the device mesh uuid or another thing ? If another, can I get it by broadcasting some commands ?

Regards