MQTT client is disconnected and cannot reconnect after sending message

[gavinheale]

I am testing the mqtt functionality using MQTTX (https://mqttx.app/) and the setup described in the intro (https://docs.aklivity.io/zilla/next/tutorials/mqtt/mqtt-intro.html).

I am connecting to the zilla broker using the address mqtt://localhost:7183

I can connect successfully and receive messages but when I send a message, I am automatically disconnected and the reconnects do not work.

I dont see anything in the zilla logs using the docker logs command.

I get the following log from MQTTX

[2023-12-06 17:28:16] [INFO] Message Arrived with topic: zilla
[2023-12-06 17:28:16] [INFO] Zilla message arrived: message added "message_a1f68ecf-3a0b-4fab-9856-264f001b3ded" and added to topic: "zilla", payload: "Hello World MQTTX 3" MQTT.js onMessageArrived trigger with Properties: undefined
[2023-12-06 17:28:16] [INFO] Zilla connect close, MQTT.js onClose trigger
[2023-12-06 17:28:20] [INFO] Zilla reconnect: 0 times retry
[2023-12-06 17:28:20] [INFO] Zilla connect close, MQTT.js onClose trigger
[2023-12-06 17:28:24] [INFO] Zilla reconnect: 1 times retry
[2023-12-06 17:28:25] [INFO] Zilla connect close, MQTT.js onClose trigger
[2023-12-06 17:28:29] [INFO] Zilla reconnect: 2 times retry
[2023-12-06 17:28:29] [INFO] Zilla connect close, MQTT.js onClose trigger
[2023-12-06 17:28:33] [INFO] Zilla reconnect: 3 times retry
[2023-12-06 17:28:33] [INFO] Zilla connect close, MQTT.js onClose trigger
[2023-12-06 17:28:37] [INFO] Zilla reconnect: 4 times retry
[2023-12-06 17:28:37] [INFO] Zilla connect close, MQTT.js onClose trigger
[2023-12-06 17:28:41] [INFO] Zilla reconnect: 5 times retry
[2023-12-06 17:28:41] [INFO] Zilla connect close, MQTT.js onClose trigger
[2023-12-06 17:28:45] [INFO] Zilla reconnect: 6 times retry
[2023-12-06 17:28:45] [INFO] Zilla connect close, MQTT.js onClose trigger
[2023-12-06 17:28:49] [INFO] Zilla reconnect: 7 times retry
[2023-12-06 17:28:50] [INFO] Zilla connect close, MQTT.js onClose trigger
[2023-12-06 17:28:54] [INFO] Zilla reconnect: 8 times retry
[2023-12-06 17:28:54] [INFO] Zilla connect close, MQTT.js onClose trigger
[2023-12-06 17:28:58] [INFO] Zilla reconnect: 9 times retry
[2023-12-06 17:28:58] [INFO] Zilla connect close, MQTT.js onClose trigger
[2023-12-06 17:29:02] [INFO] Zilla reconnect: 10 times retry
[2023-12-06 17:29:02] [INFO] Zilla connect close, MQTT.js onClose trigger
[2023-12-06 17:29:06] [WARN] Connection maxReconnectTimes limit, stop retry
[2023-12-06 17:29:06] [ERROR] Zilla connect fail, MQTT.js onError trigger, Error: client disconnecting
at MqttClient._checkDisconnecting (/Applications/MQTTX.app/Contents/Resources/app.asar/node_modules/mqtt/lib/client.js:577:26)
at MqttClient.subscribe (/Applications/MQTTX.app/Contents/Resources/app.asar/node_modules/mqtt/lib/client.js:723:12)
at MqttClient._resubscribe (/Applications/MQTTX.app/Contents/Resources/app.asar/node_modules/mqtt/lib/client.js:1747:16)
at deliver (/Applications/MQTTX.app/Contents/Resources/app.asar/node_modules/mqtt/lib/client.js:340:14)
at MqttClient. (/Applications/MQTTX.app/Contents/Resources/app.asar/node_modules/mqtt/lib/client.js:369:5)
at MqttClient.emit (events.js:327:22)
at MqttClient._onConnect (/Applications/MQTTX.app/Contents/Resources/app.asar/node_modules/mqtt/lib/client.js:1768:10)
at MqttClient._handleConnack (/Applications/MQTTX.app/Contents/Resources/app.asar/node_modules/mqtt/lib/client.js:1386:10)
at MqttClient._handlePacket (/Applications/MQTTX.app/Contents/Resources/app.asar/node_modules/mqtt/lib/client.js:549:12)
at work (/Applications/MQTTX.app/Contents/Resources/app.asar/node_modules/mqtt/lib/client.js:438:12)
at Writable.writable._write (/Applications/MQTTX.app/Contents/Resources/app.asar/node_modules/mqtt/lib/client.js:452:5)
at doWrite (/Applications/MQTTX.app/Contents/Resources/app.asar/node_modules/mqtt/node_modules/readable-stream/lib/_stream_writable.js:409:139)
at writeOrBuffer (/Applications/MQTTX.app/Contents/Resources/app.asar/node_modules/mqtt/node_modules/readable-stream/lib/_stream_writable.js:398:5)
at Writable.write (/Applications/MQTTX.app/Contents/Resources/app.asar/node_modules/mqtt/node_modules/readable-stream/lib/_stream_writable.js:307:11)
at Socket.ondata (internal/streams/readable.js:719:22)
at Socket.emit (events.js:315:20)

[bmaidics]

Hi @gavinheale ,
Thanks for filing the issue.
If I understood correctly you

1. opened a connection using MQTTX and subscribed to a topic filter.
2. opened another connection, where you produced into this topic -> successfully received on connection 1
3. produce message using client1, and you get disconnected.

I've tried it using these steps with the mqtt intro, and it was all working, so maybe I misunderstood your use case. Can you elaborate a little bit more?

• What mqtt version are you using? (I used v5)
• What is the max qos you're subscribing?
• What's the qos you're producing?
• Is it an intermittent issue or you're reproducing it constantly?

I can see in the payload "Hello World MQTTX 3". Based on this, maybe you're using V3 protocol? Note that we're only supporting v3.1.1 and v5 right now.

[gavinheale]

Hi @bmaidics,

I just reproduced this using the following steps

1. start a clean server using "docker compose up -d"
2. subscribe to messages using mosquitto
3. subscribe to messages using MQTTX
4. send a test message from mosquitto - both clients receive it
5. send a test message from MQTTX - both clients receive it but MQTTX is disconnected and cannot reconnect

To answer your questions

• I am using mqtt version 5 (see screen shots and logs)
• qos 2 I believe
• qos 2
• can be reproduced constantly

Here is the output from subscribing using mosquitto

(base) MacBook-Pro:logs gavin$ docker run -it --rm eclipse-mosquitto mosquitto_sub -V 'mqttv5' --topic 'zilla' --host 'host.docker.internal' --port 7183 --debug
Client null sending CONNECT
Client 5afed7bb-6886-4dad-900a-770918662e23 received CONNACK (0)
Client 5afed7bb-6886-4dad-900a-770918662e23 sending SUBSCRIBE (Mid: 1, Topic: zilla, QoS: 0, Options: 0x00)
Client 5afed7bb-6886-4dad-900a-770918662e23 received SUBACK
Subscribed (mid: 1): 0
Client 5afed7bb-6886-4dad-900a-770918662e23 sending PINGREQ
Client 5afed7bb-6886-4dad-900a-770918662e23 received PINGRESP
Client 5afed7bb-6886-4dad-900a-770918662e23 received PUBLISH (d0, q0, r0, m0, 'zilla', ... (21 bytes))
Test 1 from mosquitto
Client 5afed7bb-6886-4dad-900a-770918662e23 sending PINGREQ
Client 5afed7bb-6886-4dad-900a-770918662e23 received PINGRESP
Client 5afed7bb-6886-4dad-900a-770918662e23 received PUBLISH (d0, q0, r0, m0, 'zilla', ... (18 bytes))
Test 1 from MQTTX
Client 5afed7bb-6886-4dad-900a-770918662e23 sending PINGREQ
Client 5afed7bb-6886-4dad-900a-770918662e23 received PINGRESP
^CClient 5afed7bb-6886-4dad-900a-770918662e23 sending DISCONNECT
(base) MacBook-Pro:logs gavin$

Here is the log from MQTTX

bash-3.2$ tail -f log
[2023-12-07 11:15:31] [INFO] APP init
[2023-12-07 11:16:01] [INFO] MQTTX client with ID 087054be-06b2-467b-bc91-3c5f5e52dea6 assigned
[2023-12-07 11:16:01] [INFO] Connect client Zilla, MQTT/TCP connection: mqtt://localhost:7183 with Properties: {"sessionExpiryInterval":0,"receiveMaximum":null,"maximumPacketSize":null,"topicAliasMaximum":null,"requestResponseInformation":null,"requestProblemInformation":null,"authenticationMethod":null}
[2023-12-07 11:16:04] [INFO] Zilla connect success, MQTT.js onConnect trigger
[2023-12-07 11:16:04] [INFO] Topic: zilla is resubscribing
[2023-12-07 11:16:04] [INFO] Saved topic: zilla
[2023-12-07 11:16:04] [INFO] Topic: zilla successfully subscribed, Subscription Identifier: null, No Local flag: false, Retain as Published flag: false, Retain Handling: 0
[2023-12-07 11:16:59] [INFO] Message Arrived with topic: zilla
[2023-12-07 11:16:59] [INFO] Zilla message arrived: message added "message_efbf3db7-de15-4930-a2fd-d662bfcaebcd" and added to topic: "zilla", payload: "Test 1 from mosquitto" MQTT.js onMessageArrived trigger with Properties: undefined
[2023-12-07 11:17:56] [INFO] Message Arrived with topic: zilla
[2023-12-07 11:17:56] [INFO] Zilla message arrived: message added "message_7ed7cd4d-e7ad-40ec-a09a-4a91d16d93c4" and added to topic: "zilla", payload: "Test 1 from MQTTX " MQTT.js onMessageArrived trigger with Properties: undefined
[2023-12-07 11:17:56] [INFO] Zilla connect close, MQTT.js onClose trigger
[2023-12-07 11:18:00] [INFO] Zilla reconnect: 0 times retry
[2023-12-07 11:18:00] [INFO] Zilla connect close, MQTT.js onClose trigger
[2023-12-07 11:18:04] [INFO] Zilla reconnect: 1 times retry
[2023-12-07 11:18:04] [INFO] Zilla connect close, MQTT.js onClose trigger
[2023-12-07 11:18:08] [INFO] Zilla reconnect: 2 times retry
[2023-12-07 11:18:08] [INFO] Zilla connect close, MQTT.js onClose trigger
[2023-12-07 11:18:12] [INFO] Zilla reconnect: 3 times retry
[2023-12-07 11:18:13] [INFO] Zilla connect close, MQTT.js onClose trigger
[2023-12-07 11:18:17] [INFO] Zilla reconnect: 4 times retry
[2023-12-07 11:18:17] [INFO] Zilla connect close, MQTT.js onClose trigger
[2023-12-07 11:18:21] [INFO] Zilla reconnect: 5 times retry
[2023-12-07 11:18:21] [INFO] Zilla connect close, MQTT.js onClose trigger
[2023-12-07 11:18:25] [INFO] Zilla reconnect: 6 times retry
[2023-12-07 11:18:25] [INFO] Zilla connect close, MQTT.js onClose trigger
[2023-12-07 11:18:29] [INFO] Zilla reconnect: 7 times retry
[2023-12-07 11:18:29] [INFO] Zilla connect close, MQTT.js onClose trigger
[2023-12-07 11:18:33] [INFO] Zilla reconnect: 8 times retry
[2023-12-07 11:18:33] [INFO] Zilla connect close, MQTT.js onClose trigger
[2023-12-07 11:18:37] [INFO] Zilla reconnect: 9 times retry
[2023-12-07 11:18:37] [INFO] Zilla connect close, MQTT.js onClose trigger
[2023-12-07 11:18:41] [INFO] Zilla reconnect: 10 times retry
[2023-12-07 11:18:41] [INFO] Zilla connect close, MQTT.js onClose trigger
[2023-12-07 11:18:45] [WARN] Connection maxReconnectTimes limit, stop retry
[2023-12-07 11:18:45] [ERROR] Zilla connect fail, MQTT.js onError trigger, Error: client disconnecting
at MqttClient._checkDisconnecting (/Applications/MQTTX.app/Contents/Resources/app.asar/node_modules/mqtt/lib/client.js:577:26)
at MqttClient.subscribe (/Applications/MQTTX.app/Contents/Resources/app.asar/node_modules/mqtt/lib/client.js:723:12)
at MqttClient._resubscribe (/Applications/MQTTX.app/Contents/Resources/app.asar/node_modules/mqtt/lib/client.js:1747:16)
at deliver (/Applications/MQTTX.app/Contents/Resources/app.asar/node_modules/mqtt/lib/client.js:340:14)
at MqttClient. (/Applications/MQTTX.app/Contents/Resources/app.asar/node_modules/mqtt/lib/client.js:369:5)
at MqttClient.emit (events.js:327:22)
at MqttClient._onConnect (/Applications/MQTTX.app/Contents/Resources/app.asar/node_modules/mqtt/lib/client.js:1768:10)
at MqttClient._handleConnack (/Applications/MQTTX.app/Contents/Resources/app.asar/node_modules/mqtt/lib/client.js:1386:10)
at MqttClient._handlePacket (/Applications/MQTTX.app/Contents/Resources/app.asar/node_modules/mqtt/lib/client.js:549:12)
at work (/Applications/MQTTX.app/Contents/Resources/app.asar/node_modules/mqtt/lib/client.js:438:12)
at Writable.writable._write (/Applications/MQTTX.app/Contents/Resources/app.asar/node_modules/mqtt/lib/client.js:452:5)
at doWrite (/Applications/MQTTX.app/Contents/Resources/app.asar/node_modules/mqtt/node_modules/readable-stream/lib/_stream_writable.js:409:139)
at writeOrBuffer (/Applications/MQTTX.app/Contents/Resources/app.asar/node_modules/mqtt/node_modules/readable-stream/lib/_stream_writable.js:398:5)
at Writable.write (/Applications/MQTTX.app/Contents/Resources/app.asar/node_modules/mqtt/node_modules/readable-stream/lib/_stream_writable.js:307:11)
at Socket.ondata (internal/streams/readable.js:719:22)
at Socket.emit (events.js:315:20)
[2023-12-07 11:18:45] [INFO] Zilla connect success, MQTT.js onConnect trigger
[2023-12-07 11:18:46] [INFO] Topic: zilla is resubscribing
[2023-12-07 11:18:46] [ERROR] Topic: subscribe error, Error: client disconnecting
^C

[bmaidics]

Thanks @gavinheale , now I could reproduce the issue. We're working on it and update you here once it's fixed

[jfallows]

@gavinheale fyi - fix released in 0.9.61

[gavinheale]

Thanks for the quick response. I pulled the release and all looks good now.