Viewing the potential changes when changing the environment on a Puppet agentis challenging - much can be altered, and often the only way to know what willchange is to _actually_ run it. Using octocatalog-diff (from GitHub) andTheForeman (using a new plugin) we can now view these changes up front, in theUI, _before_ switching the agent to the new env. Please note that this talk was originally scheduled to be given at 11:00 Thetalk originally in this slot, "Next Generation Config Mgmt" by James Shubinwill now take place at 11:00. Octocatalog-diff is a commandline tool to show the differences between twopuppet environments for a specific node _before_ the node is moved to the newenv. That's great, but not everyone wants to work on the commandline In this talk we'll look at a new Foreman plugin (foreman-puppetdiff) whichbrings this functionality to the Foreman UI. We'll cover the basics ofoctocatalog-diff (installation, uses, limitations) and then show how to set upthe Foreman plugin and use it in the UI.