nrf SDK IOT MQTT Publisher example, can't ping from bt0 and interface go down

RE: nrf SDK IOT MQTT Publisher example, can't ping from bt0 and interface go down

Moritz — Wed, 01 Jul 2020 14:58:57 GMT

Hi!

Did you solve the disconnection problem? If yes, could you explain how?
I have the same problem with with a different iot example from the sdk.

RE: nrf SDK IOT MQTT Publisher example, can't ping from bt0 and interface go down

Miafiaj — Wed, 13 Mar 2019 15:29:29 GMT

I've succeeded into connecting the card to the broker on the RaspberryPi but the interface bt0 still disconnects even if I spam the publication to avoid timeout :

RE: nrf SDK IOT MQTT Publisher example, can't ping from bt0 and interface go down

Miafiaj — Wed, 13 Mar 2019 13:39:00 GMT

Thank you very much for your quick answer and for the information about multiple connections. I used a second card because I didn't succeed to use the example with the first one, but using multiple cards was my objective for later.

I've set the variable to 0 and I can now ping my card from bt0 but stil get "Address unreachable" for pinging anything else. And bt0 still disconnect after some time, do you know where this come from ?

RE: nrf SDK IOT MQTT Publisher example, can't ping from bt0 and interface go down

Håkon Alseth — Wed, 13 Mar 2019 11:22:07 GMT

Hi,

Since you are running a kernel that is newer than v4.12, you should set this define to '0' (its default set to '1'):

// </e>

// <q> BLE_6LOWPAN_LEGACY_MODE  - Enable legacy mode of IID derivation from Bluetooth Device Address and Link Layer address size determination. The legacy mode is not compatible with the RFC7668 sepcification. For the Linux Kernel versions higher or equal to 4.12 this define has to be set to 0, otherwise to 1.
 

#ifndef BLE_6LOWPAN_LEGACY_MODE
#define BLE_6LOWPAN_LEGACY_MODE 0
#endif

Do note that there's an issue with the bluetooth_6lowpan kernel module, where it only allows one connection:

https://devzone.nordicsemi.com/f/nordic-q-a/34042/multi-connection-of-ble-6lowpan-border-router/131313#131313

Kind regards,

Håkon