Drawing dependency graphs

Dependencies can get complicated quickly, and it's easy to end up with a circular dependency (where A depends on B, which depends on A) that will cause Puppet to complain and stop working. Fortunately, Puppet's --graph option makes it easy to generate a diagram of your resources and the dependencies between them, which can be a big help in fixing such problems.

Getting ready

Install the graphviz package to view the diagram files:

t@mylaptop ~ $ sudo puppet resource package graphviz ensure=installed
Notice: /Package[graphviz]/ensure: created
package { 'graphviz':
  ensure => '2.34.0-9.fc20',
}

How to do it...

Follow these steps to generate a dependency graph for your manifest:

1. Create the directories for a new trifecta module:

   ubuntu@cookbook:~/puppet$ mkdir modules/trifecta
   ubuntu@cookbook:~/puppet$ mkdir modules/trifecta/manifests
   ubuntu@cookbook:~/puppet$ mkdir modules/trifecta/files
   

2. Create the file modules/trifecta/manifests/init.pp...