AD Modernization Project : Part 1 - Upgrading Active Directory Schema

The first part in the AD Migration project will be to upgrade the active directory schema, When upgrading from Windows Active directory 2008 to 2016 upgrading the schema will add Classes & methods which are required in 2016.

Account which is used to upgrade the AD Schema will need following permissions -

1. Schema Admin.
2. Enterprise Admin.
3. Domain Admin.

The steps for upgrading the schema are as follows -

On any 2008 domain controller, Press Windows + R to open the run windows and then type adsiedit.msc and click ok -

In ADSI edit windows, Right click and click on "Connect to" -

Select "Select a well known naming context:" and in the drop down list select "Schema", then click on Ok-

 Expand the Schema and Right click on the domain CN & click on properties -

Scroll down and check the objectVersion for Windows server 2008 it should be 44 -

Below is a table of schema version for various Servers -

Windows Server	Schema Version
Windows 2000 Server	13
Windows Server 2003	30
Windows Server 2003 R2	31
Windows Server 2008	44
Windows Server 2008 R2	47
Windows Server 2012	56
Windows Server 2012 R2	69
Windows Server 2016	87
Windows Server 2019	88

To upgrade the schema, Mount the Windows Server 2016 media on the Windows Server 2008 domain controller which holds the Schema Master FSMO role (for checking which DC holds the schema master role type - netdom query fsmo in command prompt) and goto the following path in the media <ISO Mounted Directory>\Support\adprep and check for adprerp file -

  

Run command prompt as administrator -

Goto the media path and run the adprep tool to upgrade the forest schema -

Run adprep.exe /forestprep

after running this command it will take some time for the execution to complete -

On the successful execution of the command below message will be received -

"Adprep successfully updated the forest-wide information".

After this domain preparation needs to be done, command will be -

adprep.exe /domainprep /gpprep 

After successful execution of this command, run -

adprep.exe /rodcprep

After the commands have been executed successfully, check the objectVersion again from adsi edit it should now show 87 by this we can verify that the schema has been updated successfully -