mqtt.iotguru.cloud has IPv6 address in DNS, but refuses connections on IPv6

harald — Mon, 06 Feb 2023 15:23:58 +0000

I am trying to add a connection to my IoT MQTT Panel in Android. I get an error "Unable to connect to server ...(IPv6 addresses) and ECONNREFUSED".

Testing from my workstation;

$ telnet -6 mqtt.iotguru.cloud 8883
Trying 2a01:4f8:1c1c:13f8::1...
telnet: Unable to connect to remote host: Network is unreachable
$ telnet -6 mqtt.iotguru.cloud 8883
Trying 2a01:4f8:1c1c:13f8::1...
telnet: Unable to connect to remote host: Network is unreachable
$ telnet -6 mqtt.iotguru.cloud 8883
Trying 2a01:4f8:1c1c:13f8::1...
telnet: Unable to connect to remote host: Network is unreachable
$ telnet -6 mqtt.iotguru.cloud 8883
Trying 2a01:4f8:1c1c:13f8::1...
telnet: Unable to connect to remote host: Network is unreachable

It looks like the App in Android doesn't switch over to IPv4 after getting a connection refused on IPv6.

I suggest that either the IPv6 AAAA-record should be removed from DNS, or better, get IPv6 answering on the service.

Javascript MQTT Websockets Example

Jasonb — Sat, 07 Mar 2020 00:36:32 +0000

Attached is a simple html page illustrating how to use the Eclipse Paho JavaScript Client to create a MQTT connection over websockets to IoT Guru.

html.zip

Codesys help

SaulTT — Fri, 04 Oct 2019 19:00:27 +0000

I'm working with Codesys with MQTT, it has a block for use it, but I can only put the username and password, so I think i can´t publish anything, is something I can do?

MQTT server - IoT Guru Forum

mqtt.iotguru.cloud has IPv6 address in DNS, but refuses connections on IPv6

Javascript MQTT Websockets Example

Codesys help