With the release of Server 2012 R2, you can now do a direct upgrade to RDS2012 R2 without having to rebuild your environment. I am currently working on this, and will be looking to update this post soon.
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Very interesting if an in-place upgrade from RDS 2012 to RDS 2012 R2 is really possible.
I look very much forward to reading about your experience.
RDS2012 R2 definitely looks promising!
I haven’t got round to this yet, but I hope to have something to present soon.
Best regards,