Upgrade Windows on a server that has SharePoint Server installed
If you want to upgrade the version of the Windows Server operating system on a server that has SharePoint Server 2010 or later installed, use the process described below. In-place upgrade of the Windows OS with SharePoint installed is not supported.
Note If you apply updates that include only cumulative updates or service packs on a SharePoint server, you don't have to use this process.
Create a new server with the version of Windows Server you want.
Join the new server to the server farm. For more information about this step, see:
Move services to the new server as needed.
If you're using the search service application, make sure you remove the search component from the old server.
Decommission the old server.