For each new operating system release, Microsoft also has had to update the tools used by IT Pros to manage Windows servers remotely. In the old days, it was Server Manager (remember that?). These days, it's called Remote Server Administration Tools or RSAT and has Server Manager components built in. It's just like Microsoft to give lengthy titles to products that require acronyms.
RSAT has now been released so you can manage Windows Server 2012 and Windows Server 2012 R2 using a computer running Windows 8.1. If you want to manage Windows servers remotely, you have to install this tool because earlier versions will not run on Windows 8.1.
Here's the download: Remote Server Administration Tools for Windows 8.1
P.S. This tool will NOT run on any version of Windows RT.