Transferring the Schema master role to another Domain Controller is not something any administrator does on a regular basis. But when they do, the steps can be easily forgotten.
The option to transfer the schema role is not readily available in the Administrator Tool’s list. You’ll have to utilize the Microsoft Management Console (MMC). But before you access the MMC you’ll need to install the Schema snap-in. To install you’ll just have to register an existing dll.
First, log in to the DC that you’ll want to transfer the Scheme Role to. Then, open up the command prompt and type in regsvr32 schmmgmt.dll
To access your MMC type in mmc
in the Run box or search (for Windows Server 2008 and up). Once the console is opened you can now add the Scheme snap-in and change the Schema role.