MQTT-SN event: Retransmission retries limit has been reached

[Maboo]

Hi,

I am using an pca10059 as a SED together with a border router in my thread network. The SED shall publish every 5 min sensor data. That works fine. But after some time (randomly after 40 min or 6h) I get this error message via logger and I cant publish the sensor data anymore:

<info> app: MQTT-SN event: Retransmission retries limit has been reached.

<info> app: MQTT-SN event: Timed-out message: 5. Message ID: 0.

While testing where the problem lies, I added a pca10056 (SED) and got the same error at the same time for both devices.

These are my parameters for the SED devices (standard):

#define DEFAULT_CHILD_TIMEOUT    40                                         /**< Thread child timeout [s]. */
#define DEFAULT_POLL_PERIOD      1000                                       /**< Thread Sleepy End Device polling period when MQTT-SN Asleep. [ms] */
#define SHORT_POLL_PERIOD        100                                        /**< Thread Sleepy End Device polling period when MQTT-SN Awake. [ms] */
#define SEARCH_GATEWAY_TIMEOUT 5  

#define SCHED_QUEUE_SIZE      32                              /**< Maximum number of events in the scheduler queue. */
#define SCHED_EVENT_DATA_SIZE APP_TIMER_SCHED_EVENT_DATA_SIZE /**< Maximum app_scheduler event size. */

Do I have to change some timeout parameter for the gateway? Or does the thread network need at least one FTD next to the border router?

Ps: I use Linux, SDK17, VS-Code, pca10056/59

[Sigurd Hellesvik]

Hi

I have not been able to make this work yet.
But the MQTT-SN is run on the nRF5 border router from the "paho-mqttsn-gateway.service". This can be seen in "/etc/systemd/system/paho-mqttsn-gateway.service". From this file, we can see that the MQTT-SN HGateway runs from "/usr/sbin/MQTT-SNGateway".
In the same folder, you can find "/usr/sbin/MQTT-SNLogmonitor".
This relates to paho MQTT-Sn on How to monitor the gateway from a remote terminal.

Try running this Logmonitor. Do you get a log?

Regards,
Sigurd Hellesvik

[Maboo]

Hi,

that is what i get:

I set: ShearedMemory=YES;

pi@raspberrypi:/usr/sbin $ ./MQTT-SNLogmonitor
terminate called after throwing an instance of 'MQTTSNGW::Exception'
  what():  Semaphore can't be created.
Aborted

I couldn't even find one hint on the internet what that error means...

Regards,
Maboo


[Sigurd Hellesvik]

Hi

I get the same error as you.
I will contact our developers to see if i am able to find out how to print these logs, and hope to be back with more by Monday.

Regards,
Sigurd Hellesvik

[Maboo]

Perfect, thank you very much!

[Sigurd Hellesvik]

Hi

We do not seem to have any available way to print out logs for the nRF5 Border Router.

Maboo said:

unfortunately I do have some problems to get the OTBR running.

If you want help with getting this to work, let me know some details, and we can try to solve it.

Regards,
Sigurd Hellesvik