Active Directory
- By Orin Thomas
- 2/25/2026
Active Directory database optimization
There are several steps you can take to optimize your Active Directory database, including defragmenting the database, performing a file integrity check, and performing a semantic integrity check.
When you defragment the Active Directory database, a new copy of the database file, Ntds.dit, is created. You can defragment the Active Directory database or perform other operations only if the database is offline. You can take the Active Directory database offline by stopping the AD DS service, which you can do from the Update Services console or by issuing the following command from an elevated PowerShell prompt:
Stop-Service NTDS –force
You use the ntdsutil.exe utility to perform the defragmentation using the following command:
)
After the defragmentation has completed, copy the defragmented database over the original located in C:\windows\NTDS\ntds.dit and delete all log files in the C:\windows\NTDS folder.
You can check the integrity of the file that stores the database using the ntdsutil.exe by issuing the following command from an elevated prompt when the AD DS service is stopped:
To verify that the AD DS database is internally consistent, you can run a semantic consistency check. The semantic check can also repair the database if problems are detected. You can perform a semantic check using ntdsutil.exe by issuing the following command:
)