Both ActiveMQ and RabbitMQ (the supported middleware brokers for MCollective) support a mode that is known as direct addressing. Direct addressing means precisely what it sounds like. It is a mode where you define the nodes that you wish to contact without performing a discovery. You can directly communicate with the nodes by name. When working in a large environment, the ability to direct your queries to the correct machines without broadcasting them each time can help reduce the workload on your brokers and reduce network utilization. By default, direct addressing is on in the newer versions of MCollective and does not require any additional configuration. If it has been turned off, you can enable it with the following line in your configuration file:

direct_addressing = 1

You can enable direct addressing by either specifying a node source (text file, PuppetDB), or using the -I option for mco, as follows:

[root@puppet ~]# time mco facts architecture -I mylaptop
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