Q. How can I detect drift between an applied PowerShell DSC and the current state of a machine?
A. The simplest way to check for drift of configuration between the applied configuration and the current state is to run Test-DscConfiguration, which will return true if the configuration is correct or false if there is configuration drift. In WMF 5.0 a new cmdlet, Compare-DSCConfiguration, can show the actual drift items. Also in WMF 5.0 is the ability to add -Detailed switch to the Test-DscConfiguration cmdlet. If using a Pull server you can use this to retrieve status; more detail can be found at http://blogs.msdn.com/b/powershell/archive/2014/05/29/how-to-retrieve-node-information-from-pull-server.aspx on this approach.