ActiveMQ is an open source message broker. It is licensed by the Apache Foundation and is the recommended message broker for MCollective. ActiveMQ is configured by the activemq.xml configuration file (usually located in /etc/activemq).

It is possible that there may be a disconnect between your MCollective configuration and the ActiveMQ configuration. To check the port on which ActiveMQ is running the STOMP listener, look for the transportConnector line, which should look like this:

<transportConnector name="stomp+nio" uri="stomp://0.0.0.0:61613"/>

The uniform resource identifier (URI) specifies the connector that should be used. In the preceding line, the 0.0.0.0 address means that ActiveMQ will listen on all the interfaces and addresses on the server. For instance, if the address is 127.0.0.1, then only local connections will be allowed, and you will not be able to connect to the broker from another machine. The port specified in the preceding line of code is 61613...