When you choose not to force the replication, you may risk a loss of linked attributes, such as group memberships, on replication partners after the normal Active Directory replication transfers the undeletion to all domain controllers.
For example, when you select a user to be undeleted, with the user being a member of a certain group, and choose not to have the wizard force the replication, the results of the restore on the representation of the user’s group memberships may vary. These variations are based on which objects replicate first after the wizard completes the restore.
If the undeletion of the user replicates first, then the group membership information of both the group (the members it contains) and the user (the groups he or she belongs to) will be represented correctly.
If the restore of the group replicates first, the replication partners will drop the addition of the (locally) deleted user from the group membership. The only exception to this is the user’s primary group, which is always represented correctly from both the user and group reference.
The wizard marks the undeleted objects so that they are replicated in a proper sequence. However, making changes to them before the replication is completed may break the proper sequence. Skip the replication enforcement if you are sure that no changes will be made to the restored objects until those objects are replicated to all domain controllers within the domain. Optionally, you may have the wizard force the incremental replication on the final step. You might also force the replication with a different tool, or wait for replication to occur on normal schedule.
In addition, you might skip the replication enforcement if you undelete objects whose deletions are not yet replicated within your domain. In that scenario, the objects in question are not marked as deleted on other domain controllers, which ensures the correct representation of linked attributes.
When you choose to stop the online restore operation, the wizard neither forces the replication nor restores linked attributes.
This choice implies that you wait until the undeleted objects are replicated to all domain controllers, and then restore those objects once more using the wizard. In that scenario, the second path of the wizard is used to restore the linked attributes on the undeleted objects. Stop the operation if the enforcement of replication in your domain is inadmissible for some reasons, but you want to be sure that linked attributes be represented correctly on all domain controllers.
Note that some AD DS and AD LDS (ADAM) object attributes cannot be restored by using Recovery Manager for Active Directory. For more information on these attributes, see Quest Knowledge Base Article 59039 “AD DS and AD LDS Object Attributes That Recovery Manager for Active Directory Cannot Restore” at support.quest.com.
The following table contains performance test results of agentless and agent-based restore operations on the machine running Windows Server 2008 R2. The agent-based restore is performed by a single Restore Agent instance.
Operating System: Windows Server 2008 R2
CPU: 2 x Intel Xeon E5-2651 v2 1,8 GHz
Number of objects - Required time
1000 - 20 - 40 sec
10000 - 4 - 6 min
50000 - 23 - 34 min
Number of objects - Required time
1000 - 40 - 70 sec
10000 - 6 - 10 min
50000 - 30 - 50 min
The method that uses LDAP functions is referred to as agentless method. The agentless method has both advantages and limitations. The use of LDAP functions makes the wizard operations less intrusive on the domain controller. Also, you can deliberately choose the target domain controller and you can perform restore and compare operations without having administrative access to the target domain controller.
However, some object attributes, such as User Password and SID History, cannot be compared or restored.
The ability to perform an online restore using the agentless method builds on the Restore Deleted Objects feature. This feature extends the LDAP API to enable the restoration of deleted objects. However, this feature restores only the essential attributes required for the object's existence. Other attributes, such as those relating to membership in security and distribution groups, must be restored from a backup.
With the agentless method, you can perform a restore without having administrative access to the target domain controller. For more information, see Performing a restore without having administrator privileges.
In the Online Restore Wizard, on the Domain Access Options page, make sure the Use agentless method to access domain controller check box is selected. This ensures that only LDAP functions are used to access the domain controller.