Preventing auto cleanup of the rules

The rules on the Chef server node object will be removed upon successfull execution 
of the cookbook. The point of cleaning up is to avoid stale rules that could be 
deleted from the definitions (roles & cookbooks) but survive in the node attributes 
forever.

You can change this behaviour. One of the scenarios where you would like to do so 
would be applying the rules from outside of cookbooks, with an 
external tool perhaps.