How to set up Mosquitto bridging configuration?

Question

I wanted to set up a test configuration of Mosquitto. For one configuration file, I wrote only this:

listener 1883

I started a server with this config file, and it started successfully.

The second config file has the following:

listener 1884
connection test
address 127.0.0.1:1883

When I try to start the server with this, I get the following error message:

Error: Invalid bridge configuration.
Error: Unable to open configuration file.

It does not matter whether I try it with or without the other server running, or if I try an external address or a local one.

Answer 1

You need to provide a topic section to your bridge to tell the broker which topics to bridge.

eg

listener 1884
connection test
address 127.0.0.1:1883
topic foo/# in

This will bridge into the second broker all topics starting foo/ from the first broker.

Looks at the mosquitto.conf man page for more details about the topic keyword