Your company hasa main officeand a branch office.
The network contains an Active Directory forest.
The forest containsthree domains.
The branch officecontains one domain controllernamed DC5.
DC5is configured as a global catalog server, a DHCP server, and a file server.
You remove the global catalog from DC5.
You need to reduce the size of the Active Directory database on DC5.
The solution must minimize the impact on all users in the branch office.
What should you do first?

A.
Start DC5 in Safe Mode.

B.
Start DC5 in Directory Services Restore Mode.

C.
On DC5, start the Protected Storage service.

D.
On DC5, stop the Active Directory Domain Servicesservice.

Explanation:
http://allcomputers.us/windows_server/windows-server-2008-r2—manage-the-active-directory-database-%
28part-2%29—defragment-the-directory-database—audit-active-directory-service.aspx
Windows Server 2008 R2 : Manage the Active Directory Database (part 2) – Defragment the Directory
Database & Audit Active Directory Service
3. Defragment the Directory Database
A directory database gets fragmented as you add, change, and delete objects to your database. Like anyfile
system–based storage, as the directory database is changed and updated, fragments of disk space will build up
so it needs to be defragmented on a routine basis to maintain optimal operation. By default, Active Directory
performs an online defragmentation of the directorydatabase every 12 hours with the garbage collection
process, an automated directory database cleanup, and IT pros should be familiar with it. However, online
defragmentation does not decrease the size of the NTDS.DIT database file. Instead, it shuffles the data around
for easier access. Depending on how much fragmentation you actually have in the database, running an offline
defragmentation—which does decrease the size of thedatabase—could have a significant effect on the overall
size of your NTDS.DIT database file.
There is a little problem associated with defragmenting databases. They have to be taken offline in order to
have the fragments removed and the database resized. In Windows Server 2008 R2, there is a great feature
that allows you to take the database offline without shutting down the server. It’s called RestartableActive
Directory, and it could not be much easier to stop and start your directory database than this. Figure4 shows
the Services tool and how you can use it to stop the Active Directory service.
1. Start the Services tool from the Control Panel.
2. Right-click Active Directory Domain Services, and select Stop.

Figure 4. You can use the Services tool to stop and restart Active Directory.
That’s it! Now when you stop Active Directory Domain Services, any other dependent services will also be
stopped. Keep in mind that while the services are stopped, they cannot fulfill their assigned role in your network.
The really cool thing about Restartable AD is that while the directory services and its dependent services are
stopped, other services on the local machine are not. So, perhaps you have a shared printer running onyour
DC. Print services still run, and print operations do not stop. Nice!
3.1. Offline Directory Defragmentation
Now that you have stopped Active Directory services, it is time to get down to the business of offline
defragmentation of the directory database:
1. Back up the database.
2. Open a command prompt, and type NTDSUTIL.
3. Type ACTIVATE INSTANCE NTDS.
4. Type FILES, and press Enter.
5. Type INFO, and press Enter. This will tell you the current location of the directory database, its size, and the
size of the associated log files. Write all this down.
6. Make a folder location that has enough drive space for the directory to be stored.
7. Type COMPACT TO DRIVE:\DIRECTORY, and press Enter. The drive and directory are the locations you
set up in step 5. If the drive path contains spaces, put the whole path in quotation marks, as in “C:\database
defrag”.
A new defragmented and compacted NTDS.DIT is created in the folder you specified.
8. Type QUIT, and press Enter.
9. Type QUIT again, and press Enter to return to thecommand prompt.
10.If defragmentation succeeds without errors, follow the NTDSUTIL prompts.
11.Delete all log files by typing DEL x:\pathtologfiles\*.log where x is the drive letter of your drive.
12.Overwrite the old NTDS.DIT file with the new one. Remember, you wrote down its location in step 4.
13.Close the command prompt.
14.Open the Services tool, and start Active Directory Domain Services.
Defragmenting your directory database using the offline NTDSUTIL process can significantly reduce the size of
your database depending on how long it has been since your last offline defrag. The hard thing about offline
defrag is that every network is different, so making recommendations about how often to use the offline defrag
process is somewhat spurious. I recommend you get to know your directory database. Monitor its size and
growth. When you think it is appropriate to defragment offline, then do it. A pattern will emerge for you, and you
will find yourself using offline defragmentation ona frequency that works well for your network and your
directory database. One of the cool things about offline defragmentation is that if you should happen to have an
error occur during the defragmentation process, youstill have your original NTDS.DIT database in place and
can continue using it with no problems until you can isolate and fix any issues.