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The first thought that came to mind: since we're running several Linux servers already on IPv6-only, would it be possible to run a Windows server also on IPv6?
Last year my intern Joris Claassen has proved that it was possible to run a basic VMware Vsphere cluster on IPv6 only, and that included a Windows box as well. So things look bright.
While Windows Server 2012 has been released recently, we can not use it (yet), because the latest version of Windows that our current VMware setup (ESXi 4.1) supports as guest OS is Server 2008 R2.
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