Requirements and Recommendations before installing SCCM 2012 R2
Prepare to Upgrade to Configuration Manager 2012 R2
Step-by-Step SCCM 2012 R2 SP1 Upgrade Guide
Managing SCCM client agent by David Papkin
Installing System Center Configuration Manager 2012 SP1 on Windows Server 2012 – Automation Planet
Server 2012 In placed upgrade to Server 2016 - SCCM Site Server - YouTube
Step by Step : How to Deploy System Center 2012 R2 Configuration Manager ( SCCM) in Windows Server 2012 R2 | Just a random "Microsoft Server / Client Tech" info..