The Marionette Collective (MCollective for short) is a tool for system administration. It can run commands on large numbers of servers in parallel, and uses a broadcast architecture so that you can administer a large network without the need for a central master server or asset database.
Each server runs an MCollective daemon that listens for requests, and can execute commands locally or return information about the server. This can be used to filter the list of target servers. So, for example, you could use MCollective to execute a given command on all servers that match certain criteria.
You can think of MCollective as a complement to Puppet (though it also works fine with Chef and other configuration management systems). For ...