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To achieve the goal of configuring Data1 to run a Server Core Installation of Windows Server 2012 R2 Datacenter with the minimum amount of administrative effort, you should perform an online servicing using the DISM tool. The command would be `DISM /online /Set-Edition:ServerDatacenter /ProductKey:XXXXX-XXXXX-XXXXX-XXXXX-XXXXX /AcceptEula`. This option allows you to upgrade the edition without requiring a reinstallation or significant downtime, making it the most efficient method.