Under what conditions can I receive a Zigbee ZB_NWK_SIGNAL_NO_ACTIVE_LINKS_LEFT?

[johnmartin117]

I'm using Segger Embedded Studio 3.52, nRF SDK for Thread and Zigbee v3, nRF52840-Preview-DK

I have a Zigbee Coordinator and Zigbee Router that work great at my home office. However, when I bring this same setup to my companies office, I get the ZB_NWK_SIGNAL_NO_ACTIVE_LINKS_LEFT signal randomly. Once I get this signal, the only way to recover is to restart the board.

1) Under what conditions should I receive the ZB_NWK_SIGNAL_NO_ACTIVE_LINKS_LEFT signal?

2) If I do receive the ZB_NWK_SIGNAL_NO_ACTIVE_LINKS_LEFT signal, what can I do to reestablish the Zigbee connection?

Thanks,

John Martin

[Kenneth]

I notice you are using a preview kit, those aren't recommended for development anymore, they contain early engineering samples with various issues that was fixed before transferred to production. But to answer your question:

 ZB_NWK_SIGNAL_NO_ACTIVE_LINKS_LEFT,    /*!< Notifies the application about the Neighbor Table expiration.
                                          * It means that the neighbor devices did not send 
                                          * the Link Status messages for @ref ZB_NWK_ROUTER_AGE_LIMIT * @ref ZB_NWK_LINK_STATUS_PERIOD seconds.
                                          * @parblock
                                          * When generated:
                                          *  - All routes expired (usually when the link is down).
                                          * 
                                          * Status codes: 
                                          *  - RET_OK: All routers expired.
                                          *  - Does not return error status.
                                          * 
                                          * Signal parameters: 
                                          *  - none
                                            @endparblock */ 

[johnmartin117]

Thanks for your reply Kenneth!

We are building a custom board based on the nRF52840. The preview kit is being used simply until our board is ready. Are you saying that I should stop developing on it?

I looked at zboss_api_zdo.h and read the description there before I sent my question. That description leaves a lot to be desired. Like what do I do to the Router when I receive this signal? How can I re-establish a Zigbee connection? It says it usually happens with the link is down, but what other events can also cause it? How do I bring the link back up? From what I can see, nothing on the Coordinator changes, so is this a Router issue or could the problem be at the Coordinator? The Router and Coordinator are about 6 feet apart. I don't move them or otherwise change anything, yet this issue happens sporadically.

Once I get this signal, the only way that I've been able to re-establish the Zigbee link is to restart the board. Obviously that isn't a long term solution.

Thanks,

John Martin

[Kenneth]

johnmartin117 said:

Are you saying that I should stop developing on it?

 Yes, definitively. Regarding your other comments I will report them as suggestions for improvements.

[johnmartin117]

I've worked with our hardware developer and I am now using a custom board based off of the Rigado Wireless Module (https://www.rigado.com/wireless-modules/). I am getting the same result. I randomly receive the ZB_NWK_SIGNAL_NO_ACTIVE_LINKS_LEFT signal. So it doesn't appear to be related to the preview kit.

My second question is still relevant: If I do receive the ZB_NWK_SIGNAL_NO_ACTIVE_LINKS_LEFT signal, what can I do to reestablish the Zigbee connection?

Any help? John

[AndreasF]

Hi John.

Do you happen to have sniffer logs when you receive this signal?

The  ZB_NWK_SIGNAL_NO_ACTIVE_LINKS_LEFT signal is generated when no other routers are present in the network and the links to them has expired.

What other devices do you have in the network, do you have another router?

Best regards,

Andreas