Take a look on below link
The article relates to SQL Server 2012, not Windows 2012 R2 w/ SQL 2008 R2. I would assume it IS supported because its a minor revision to Windows 2012. Guess there's one way to find out...
- Proposed as answer by Allen Li - MSFTMicrosoft contingent staff, Moderator Tuesday, October 01, 2013 8:46 AM
We can monitor Microsoft site about Windows Server 2012 R2 and get detail information about it after its release. Additionally, I want to share a link about using SQL Server 2008 R2 with Windows Server 2012.
Windows Server 2012 R2
Using SQL Server in Windows 8 and Windows Server 2012 environments
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