Hello
I am working on a project in which the main idea is to connect a lot of arduino in the network. I thought that MQTT would be perfect.
The central unit is the computer on which the Mosquito server is running. In addition, is runing a program to serve everyone Arduino working in the network.
Of course, this is a very early phase of the project. During the first tests I connected with only one Arduino and everything worked satisfactorily. Arduino have to receive commands from a computer and send reports.
I used Arduino WeMos D1 mini (ESP8266) and I think the most popular library "PubSubClient" to write a program for Arduino.
The problem is when I connect two (or more) arduino .... In the network, of course, they received their own IP. They should subscribe to the same Topic ... because they work together. Unfortunately, they have a problem with the connection ...
Below part of the sample program from library:
void reconnect() {
// Loop until we're reconnected
while (!client.connected()) {
Serial.print("Attempting MQTT connection...");
// Attempt to connect
if (client.connect("ESP8266Client")) {
Serial.println("connected");
// Once connected, publish an announcement...
client.publish("xxx", "hello world");
// ... and resubscribe
client.subscribe("xxx");
} else {
Serial.print("failed, rc=");
Serial.print(client.state());
Serial.println(" try again in 5 seconds");
// Wait 5 seconds before retrying
delay(5000);
}
}
}
In Serial port monitor I have only "Attempting MQTT connection..." from both Arduino.
When I switches off one of them, the other starts to work correctly.
Maybe someone knows what I'm doing wrong ...?
Thank you for every help.
I really didn't think about the name of it.