SCCM 2012 - Upgrade your SCCM 2012 SP1 environment to SCCM 2012 R2

If you are interested to upgrade your SCCM 2012 SP1 Site I would like to suggest you the following article that explain you, step by step, how to solve this issue:

http://www.deploymentresearch.com/Research/tabid/62/EntryId/117/A-Geeks-Guide-for-upgrading-to-ConfigMgr-2012-R2-and-MDT-2013.aspx