Can't reconnect to MQTTSN gateway

RE: Can't reconnect to MQTTSN gateway

Mary — Thu, 07 Nov 2019 19:58:58 GMT

I was able to download and compile the latest MQTTSN-Gateway. This solved my problem. I was able to have a node reboot every 10 seconds and successfully reconnect for several hours.

Instructions for compiling the MQTTSN-Gateway are here.

Here's what I did:

Before compiling on the RaspberryPi, first install ssl-dev. This adds header files, etc so you can compile OpenSSL dependent code..

$ sudo apt-get update
$ sudo apt-get install libssl-dev

Create a working directory. I used /home/pi/Projects.

Next, build the gateway:

$ cd ~
$ mkdir Projects
$ cd Projects
$ git clone -b experiment https://github.com/eclipse/paho.mqtt-sn.embedded-c   
$ cd paho.mqtt-sn.embedded-c/MQTTSNGateway       
$ make SENSORNET=udp6 
$ make install INSTALL_DIR=/home/pi/Projects/MQTTSNGateway_v1.3.1 CONFIG_DIR=/home/pi/Projects/MQTTSNGateway_v1.3.1   
$ make clean

Stop the currently running gateway:

$ sudo systemctl stop paho-mqttsn-gateway.service

Edit the service file:

$ sudo nano /etc/systemd/system/paho-mqttsn-gateway.service

Change the ExecStart line to explicitly specify the configuration file:

ExecStart=/usr/sbin/MQTT-SNGateway -f /etc/paho-mqtt-sn-gateway.conf

Copy the predefinedTopics.conf file from the CONFIG_DIR to /etc or add a new file for predefined topics and edit as needed.

$ sudo nano /etc/predefinedTopic.conf

Make a backup of the original executable and copy the new one to /usr/sbin:

$ sudo cp /usr/sbin/MQTT-SNGateway /usr/sbin/MQTT-SNGateway_v1.0.1

$ sudo cp /home/pi/Projects/MQTTSNGateway_v1.3.1/MQTT-SNGateway /usr/sbin/MQTT-SNGateway

$ make clean

Restart the gateway:

$ sudo systemctl start paho-mqttsn-gateway.service

Viewing the systemd log will show the gateway activity.

$ journalctl -ef

RE: Can't reconnect to MQTTSN gateway

AndreasF — Fri, 20 Sep 2019 14:34:01 GMT

Hi.

Still waiting on reply from the development team.

Best regards,

Andreas

RE: Can't reconnect to MQTTSN gateway

AndreasF — Wed, 18 Sep 2019 15:10:18 GMT

Hi.

Sorry for the late reply, I've been out of office for a while.

I have forwarded this to our development team to get some assistance from them.

Best regards,

Andreas

RE: Can't reconnect to MQTTSN gateway

Mary — Fri, 13 Sep 2019 13:39:14 GMT

Yes, as I mentioned above.

I've also looked at the MQTT-SNGateway code at github. There's a limit of 100 connections, after that no more can be accepted. The current version of the software provides for re-using a connection when a device re-connects after a disconnection. I wonder if this provision is missing in the 1.0.1 version that is installed on the 3.1.0 Border Router, such that after 100 Thread device reboots all connections fail.

I'd like to try the latest version of MQTT-SNGateway, and just wanted some guidance on how to do that without breaking anything.

Mary

RE: Can't reconnect to MQTTSN gateway

AndreasF — Fri, 13 Sep 2019 05:45:07 GMT

Hi.

Have you tried to update to the latest SDK, 3.1.0?

Best regards,

Andreas

RE: Can't reconnect to MQTTSN gateway

Mary — Wed, 11 Sep 2019 18:48:59 GMT

I'm wondering if just updating to the latest version of MQTT-SNGateway would help. Can you provide me with instructions on how to do that?

RE: Can't reconnect to MQTTSN gateway

AndreasF — Tue, 09 Jul 2019 10:54:08 GMT

Hi Mary.

I've forwarded your latest reply to our developers, I have to wait and see what they come up with. Note that it is holiday season so it might take some time.

Best regards,

Andreas

RE: Can't reconnect to MQTTSN gateway

Mary — Mon, 08 Jul 2019 16:06:03 GMT

Thanks.

Today, I installed the latest Border Router on the raspberry pi,3.1.0 and the same thing happened. The gateway starts refusing connections after the repeated re-connects from Dalcc970a4319322c55 .

MQTT-SNGateway is version 1.01

I searched for the error message "CONNECT message has been discarded" and found it here.

The discussion includes this code snippet from MQTTSNGWClientRecvTask.cpp:

                /* create a client */
				client = _gateway->getClientList()->createClient(_sensorNetwork->getSenderAddress(), &data.clientID, false, false);
				log(client, packet, &data.clientID);
				if (!client)
				{
                                        //char buf[128]; 
					WRITELOG("%s Client(%s) was rejected. CONNECT message has been discarded.%s\n", ERRMSG_HEADER, _sensorNetwork->getSenderAddress()->sprint(buf), ERRMSG_FOOTER);
					delete packet;
					continue;
				}

It apparently is unable to create a new client, but I have no idea why.

Mary

RE: Can't reconnect to MQTTSN gateway

AndreasF — Mon, 08 Jul 2019 13:16:48 GMT

Hi.

This requires some digging, I have asked if our developer team can take a look at it if that's ok for you.

Best regards,

Andreas

RE: Can't reconnect to MQTTSN gateway

Mary — Fri, 05 Jul 2019 15:31:45 GMT

I have reproduce the problem.

I am at the moment testing the watchdog timer function. To test the timeout function, I comment out the call to feed the watchdog timer so that the timeout and reset occurs after 5 seconds. This happens repeatedly. So, it's rebooting and reconnecting to the mqttsn gateway every 5 seconds.

After a while the gateway starts rejecting the connection. The attached file shows the mqttsn gateway log:

Client "Dal2599e811bfb8c985" is running continuously without rebooting.

Client "Dalcc970a4319322c55 " is rebooting after 5 seconds.

See line 1282 for the first client rejection.

Further down (line 1381), even the node that is not rebooting gets rejected

devzone.nordicsemi.com/.../mqtt_2D00_gateway_5F00_log_5F00_connect_5F00_rejected.txt

I know this is not a realistic scenario, but I'd like to know why the gateway starts rejecting ANY connection.

The only recovery is to stop and restart the gateway.

Mary

RE: Can't reconnect to MQTTSN gateway

AndreasF — Thu, 04 Jul 2019 08:01:31 GMT

Hi.

Great to hear that it is working :-)

Best regards,

Andreas

RE: Can't reconnect to MQTTSN gateway

Mary — Tue, 02 Jul 2019 15:45:01 GMT

I stopped and restarted mosquitto:

/etc/init.d/mosquitto stop

/etc/init.d/mosquitto start

then restarted the gateway:

sudo /usr/sbin/MQTT-SNGateway -f paho-mqtt-sn-gateway.conf &

and it ran.

Message publishing is now restored, (but all the messages from the gateway are printing to my raspberry pi console.)

RE: Can't reconnect to MQTTSN gateway

Mary — Tue, 02 Jul 2019 14:08:23 GMT

I tried killing the MQTT-SNGateway:

sudo kill -9 <PID>

then restar it:

/usr/sbin/MQTT-SNGateway

but got an error:

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

I will have to reboot. I will also download the latest image.

Mary

RE: Can't reconnect to MQTTSN gateway

AndreasF — Tue, 02 Jul 2019 08:10:05 GMT

Hi Mary.

We have a new SDK and a new border router I suggest that you start using, you can download both here.

About your issue:

Could you try to restart the MQTT-SN Gateway (only the gateway, not the whole Raspberry PI) when this issue occurs, so that we can check if the problem is still there? Should this help you the problem is likely somewhere in the gateway. If this does not work, could you try to restart mosquitto?

Best regards,

Andreas