[Mqtt client]: Failed to create socket. Connection to server mqtt.thingspeak.com:1883 failed!

[stroobandt]

First, some context: I have ample experience with successfully connecting to the popular, freemium ThingSpeak service using the standard MicroPython umqtt module.

I have carefully studied your mqtt interface as well as the ThingSpeak MQTT API and especially the ThingSpeak MQTT pitfalls.

Despite all this background, I fail to successfully connect to the ThingSpeak MQTT server. Using mqtt.status() and the REPL, I witness several connection attempts. Eventually, the following errors are printed in the REPL (the number between the parenthesis varies):

E (1786998) [Mqtt client]: Failed to create socket
E (1786999) [Mqtt client]: Connection to server mqtt.thingspeak.com:1883 failed!

The connected_cb callback function gets never called. With respect to the ThingSpeak MQTT troubleshooting page, I have tried many variations of autoreconnect=True and cleansession=True, etc.

In view of all this, I am starting to suspect a bug. I would love to see a successful ThingSpeak MQTT example in the documentation.

[carterw]

Failing to create the socket sounds unrelated to the MQTT protocol. Do you have a WiFi connection to the internet actively up and running while you are attempting to reach the MQTT server?

[stroobandt]

@carterw Yes, certainly, and I always test for it with wlan.isconnected(). I really do think it must have something to do with Loboris' implementation of mqtt. With standard umqtt and renaming the keywords, I have no issues.

[stroobandt]

@carterw There are two ways to convey MQTT messages, either over TCP or websockets.

Anyhow, I am going to close this issue now as Thingspeak admitted in a private message that they have issues with MQTT server reliability. However, there are no reliability issues when using Thingspeak's REST API.

[Josverl]

I am running into the same. I have a few network traces that indicate that the issue is caused by the LoBo built-in MQTT client requiring a \lwt which is not allowed by ThingSpeak

Lobo Built-in client Frame 256: 116 bytes on wire (928 bits), 116 bytes captured (928 bits) on interface 0 Ethernet II, Src: 62:ea:17:ea:c2:9d (62:ea:17:ea:c2:9d), Dst: IETF-VRRP-VRID_02 (00:00:5e:00:01:02) Internet Protocol Version 4, Src: 10.137.249.246, Dst: 52.54.126.159 Transmission Control Protocol, Src Port: 62310, Dst Port: 1883, Seq: 1, Ack: 1, Len: 62 MQ Telemetry Transport Protocol, Connect Command Header Flags: 0x10 (Connect Command) Msg Len: 60 Protocol Name Length: 6 Protocol Name: MQIsdp Version: MQTT v3.1 (3) Connect Flags: 0xc4 1... .... = User Name Flag: Set .1.. .... = Password Flag: Set ..0. .... = Will Retain: Not set ...0 0... = QoS Level: At most once delivery (Fire and Forget) (0) .... .1.. = Will Flag: Set .... ..0. = Clean Session Flag: Not set .... ...0 = (Reserved): Not set Keep Alive: 120 Client ID Length: 15 Client ID: mpy_mqtt_client Will Topic Length: 4 Will Topic: /lwt Will Message Length: 0 Will Message: User Name Length: 3 User Name: jos Password Length: 16 Password: U32KDACARRXDWGSF

Working Desktop client Frame 4: 101 bytes on wire (808 bits), 101 bytes captured (808 bits) on interface 0 Ethernet II, Src: 6a:45:33:f3:f8:38 (6a:45:33:f3:f8:38), Dst: Fortinet_09:1f:0c (00:09:0f:09:1f:0c) Internet Protocol Version 4, Src: 172.17.1.67, Dst: 34.235.10.220 Transmission Control Protocol, Src Port: 50463, Dst Port: 1883, Seq: 1, Ack: 1, Len: 47 MQ Telemetry Transport Protocol, Connect Command Header Flags: 0x10 (Connect Command) Msg Len: 45 Protocol Name Length: 4 Protocol Name: MQTT Version: MQTT v3.1.1 (4) Connect Flags: 0xc2 1... .... = User Name Flag: Set .1.. .... = Password Flag: Set ..0. .... = Will Retain: Not set ...0 0... = QoS Level: At most once delivery (Fire and Forget) (0) .... .0.. = Will Flag: Not set .... ..1. = Clean Session Flag: Set .... ...0 = (Reserved): Not set Keep Alive: 60 Client ID Length: 10 Client ID: client_123 User Name Length: 3 User Name: jos Password Length: 16 Password: U32KDACARRXDWGSF

[stroobandt]

@Josverl Feel free to reopen this issue. Mind you, it is not a good idea to post passwords over here!

[Josverl]

Well , the password/APIKey shown is not the real APIKey :-) And perhaps its my oversight , but I cannot see an option to re-open, only to create a new issue. Ill do that and ref this one then.

[stroobandt]

Reopened by popular demand.

[loboris]

The mqtt module was updated, the new mqtt library is now used which should solve the issue. The Wiki is updated and includes an example to connect to ThingSpeak (tested and works).