MCollective or 'Marionette Collective ' is a framework to distribute parallel commands to a cluster of computers. You can basicly compare it to remote execution except the framework is organized to work the commands in parallel. Via a simple plugin structure of ruby it is relatively easy to write your own commands. Marionette Collective works on top of a message queue broker, you can pick different flavors for the broker but the most common adoption appears to be activemq. Other brokers such as rabbitmq are supported as well. With MCollective there are basicly two configations 'server' and 'client', contrary to terminology, 'server.cfg' is used for the deamon service. In this configuration file you configure what queue on the broker the deamon connects to receive commands. In the 'server.cfg' you configure the queue on the broker to send the commands. So in short: server.cfg is for the command-line client, client.cfg is for the deamon proces