Analize: mosquitto restart loses mqtt agent topic subscriptions ?

[AlvaroVega]

A keepalive and a restart agent procedure would be a solution?

[AlvaroVega]

UL done by https://github.com/telefonicaid/iotagent-ul/blob/329cfebbe7dd6359ef13ca30075349603dfaba9a/lib/bindings/MQTTBinding.js#L134
JSON done by

iotagent-json/lib/bindings/MQTTBinding.js

Lines 134 to 153 in dd6ebde

	function recreateSubscriptions(callback) {
	config.getLogger().debug(context, 'Recreating subscriptions for all devices');
	function subscribeToTopics(topics, callback) {
	config.getLogger().debug(context, 'Subscribing to topics: %j', topics);
	mqttClient.subscribe(topics, null, function (error) {
	if (error) {
	iotAgentLib.alarms.raise(constants.MQTTB_ALARM, error);
	config.getLogger().error(context, 'GLOBAL-001: Error subscribing to topics: %s', error);
	callback(error);
	} else {
	iotAgentLib.alarms.release(constants.MQTTB_ALARM);
	config.getLogger().debug(context, 'Successfully subscribed to the following topics:\n%j\n', topics);
	if (callback) {
	callback(null);
	}
	}
	});
	}

[AlvaroVega]

related #525

[chandradeep11]

@AlvaroVega
I'm investigating this issue.

[AlvaroVega]

In this case

ota-json time=2022-02-21T12:32:54.702Z | lvl=ERROR | corr=4b9c69b5-86eb-466d-956b-2cf1c776c170 | trans=4b9c69b5-86eb-466d-956b-2cf1c776c170 | op=IOTAJSON.MQTT.Binding | from=n/a | srv=XXXX | subsrv=/YYYY | msg=GLOBAL-001: Error subscribing to topics: Error: Connection closed
pro-core-smc-iota-json-6c7f4c7764-2cvrm smc-iota-json-container at /opt/iotagent-json/node_modules/mqtt/lib/client.js:105:29
pro-core-smc-iota-json-6c7f4c7764-2cvrm smc-iota-json-container at Array.forEach ()
pro-core-smc-iota-json-6c7f4c7764-2cvrm smc-iota-json-container at flushVolatile (/opt/iotagent-json/node_modules/mqtt/lib/client.js:103:24)
pro-core-smc-iota-json-6c7f4c7764-2cvrm smc-iota-json-container at Socket. (/opt/iotagent-json/node_modules/mqtt/lib/client.js:304:5)
pro-core-smc-iota-json-6c7f4c7764-2cvrm smc-iota-json-container at Socket.emit (events.js:314:20)
pro-core-smc-iota-json-6c7f4c7764-2cvrm smc-iota-json-container at Socket.EventEmitter.emit (domain.js:506:15)
pro-core-smc-iota-json-6c7f4c7764-2cvrm smc-iota-json-container at TCP. (net.js:675:12)
pro-core-smc-iota-json-6c7f4c7764-2cvrm smc-iota-json-container at TCP.callbackTrampoline (internal/async_hooks.js:126:14) | comp=IoTAgent

it seems that iotagent tries to reconnect but mosquitto refuse it.
Maybe related with the usage of random mqtt client_id by iota, non a fixed one provided with IOTA_MQTT_CLIENT_ID