The following list describes the 5 unique FSMO roles in an Active Directory forest and the dependent operations that they perform:
- Schema master - The Schema master role is forest-wide and there is one for each forest. This role is required to extend the schema of an Active Directory forest or to run the adprep /domainprep command.
- Domain naming master - The Domain naming master role is forest-wide and there is one for each forest. This role is required to add or remove domains or application partitions to or from a forest.
- RID master - The RID master role is domain-wide and there is one for each domain. This role is required to allocate the RID pool so that new or existing domain controllers can create user accounts, computer accounts or security groups.
- PDC emulator - The PDC emulator role is domain-wide and there is one for each domain. This role is required for the domain controller that sends database updates to Windows NT backup domain controllers. The domain controller that owns this role is also targeted by certain administration tools and updates to user account and computer account passwords.
- Infrastructure master - The Infrastructure master role is domain-wide and there is one for each domain. This role is required for domain controllers to run the adprep /forestprep command successfully and to update SID attributes and distinguished name attributes for objects that are referenced across domains.
- An administrator reassigns the role by using a GUI administrative tool.
- An administrator reassigns the role by using the ntdsutil /roles command.
- An administrator gracefully demotes a role-holding domain controller by using the Active Directory Installation Wizard. This wizard reassigns any locally-held roles to an existing domain controller in the forest. Demotions that are performed by using the dcpromo /forceremoval command leave FSMO roles in an invalid state until they are reassigned by an administrator.
- The current role holder is operational and can be accessed on the network by the new FSMO owner.
- You are gracefully demoting a domain controller that currently owns FSMO roles that you want to assign to a specific domain controller in your Active Directory forest.
- The domain controller that currently owns FSMO roles is being taken offline for scheduled maintenance and you need specific FSMO roles to be assigned to a “live” domain controller. This may be required to perform operations that connect to the FSMO owner. This would be especially true for the PDC Emulator role but less true for the RID master role, the Domain naming master role and the Schema master roles.
- The current role holder is experiencing an operational error that prevents an FSMO-dependent operation from completing successfully and that role cannot be transferred.
- A domain controller that owns an FSMO role is force-demoted by using the dcpromo /forceremoval command.
- The operating system on the computer that originally owned a specific role no longer exists or has been reinstalled.
The partition for each FSMO role is in the following list:
FSMO role | Partition |
Schema | CN=Schema,CN=configuration,DC= |
Domain Naming Master | CN=configuration,DC= |
PDC | DC= |
RID | DC= |
Infrastructure | DC= |
A domain controller whose FSMO roles have been seized should not be permitted to communicate with existing domain controllers in the forest. In this scenario, you should either format the hard disk and reinstall the operating system on such domain controllers or forcibly demote such domain controllers on a private network and then remove their metadata on a surviving domain controller in the forest by using the ntdsutil /metadata cleanup command. The risk of introducing a former FSMO role holder whose role has been seized into the forest is that the original role holder may continue to operate as before until it inbound-replicates knowledge of the role seizure. Known risks of two domain controllers owning the same FSMO roles include creating security principals that have overlapping RID pools, and other problems.
Transfer FSMO roles
To transfer the FSMO roles by using the Ntdsutil utility, follow these steps:- Log on to a Windows 2000 Server-based or Windows Server 2003-based member computer or domain controller that is located in the forest where FSMO roles are being transferred. We recommend that you log on to the domain controller that you are assigning FSMO roles to. The logged-on user should be a member of the Enterprise Administrators group to transfer Schema master or Domain naming master roles, or a member of the Domain Administrators group of the domain where the PDC emulator, RID master and the Infrastructure master roles are being transferred.
- Click Start, click Run, type ntdsutil in the Open box, and then click OK.
- Type roles, and then press ENTER.
Note To see a list of available commands at any one of the prompts in the Ntdsutil utility, type ?, and then press ENTER. - Type connections, and then press ENTER.
- Type connect to server servername, and then press ENTER, where servername is the name of the domain controller you want to assign the FSMO role to.
- At the server connections prompt, type q, and then press ENTER.
- Type transfer role, where role is the role that you want to transfer. For a list of roles that you can transfer, type ? at the fsmo maintenance prompt, and then press ENTER, or see the list of roles at the start of this article. For example, to transfer the RID master role, type transfer rid master. The one exception is for the PDC emulator role, whose syntax is transfer pdc, not transfer pdc emulator.
- At the fsmo maintenance prompt, type q, and then press ENTER to gain access to the ntdsutil prompt. Type q, and then press ENTER to quit the Ntdsutil utility.
Seize FSMO roles
To seize the FSMO roles by using the Ntdsutil utility, follow these steps:- Log on to a Windows 2000 Server-based or Windows Server 2003-based member computer or domain controller that is located in the forest where FSMO roles are being seized. We recommend that you log on to the domain controller that you are assigning FSMO roles to. The logged-on user should be a member of the Enterprise Administrators group to transfer schema or domain naming master roles, or a member of the Domain Administrators group of the domain where the PDC emulator, RID master and the Infrastructure master roles are being transferred.
- Click Start, click Run, type ntdsutil in the Open box, and then click OK.
- Type roles, and then press ENTER.
- Type connections, and then press ENTER.
- Type connect to server servername, and then press ENTER, where servername is the name of the domain controller that you want to assign the FSMO role to.
- At the server connections prompt, type q, and then press ENTER.
- Type seize role, where role is the role that you want to seize. For a list of roles that you can seize, type ? at the fsmo maintenance prompt, and then press ENTER, or see the list of roles at the start of this article. For example, to seize the RID master role, type seize rid master. The one exception is for the PDC emulator role, whose syntax is seize pdc, not seize pdc emulator.
- At the fsmo maintenance prompt, type q, and then press ENTER to gain access to the ntdsutil prompt. Type q, and then press ENTER to quit the Ntdsutil utility.
Notes- Under
typical conditions, all five roles must be assigned to “live” domain
controllers in the forest. If a domain controller that owns a FSMO role
is taken out of service before its roles are transferred, you must
seize all roles to an appropriate and healthy domain controller. We
recommend that you only seize all roles when the other domain controller
is not returning to the domain. If it is possible, fix the broken
domain controller that is assigned the FSMO roles. You should
determine which roles are to be on which remaining domain controllers so
that all five roles are assigned to a single domain controller.
For more information about FSMO role placement, click the following
article number to view the article in the Microsoft Knowledge Base:
223346 FSMO placement and optimization on Windows 2000 domain controllers
- If the domain controller that formerly held any FSMO
role is not present in the domain and if it has had its roles
seized by using the steps in this article, remove it from the Active
Directory by following the
procedure that is outlined in the following Microsoft Knowledge Base
article: 216498 How to remove data in active directory after an unsuccessful domain controller demotion
- Removing domain controller metadata with the Windows 2000 version or the Windows Server 2003 build 3790 version of the ntdsutil /metadata cleanup command does not relocate FSMO roles that are assigned to live domain controllers. The Windows Server 2003 Service Pack 1 (SP1) version of the Ntdsutil utility automates this task and removes additional elements of domain controller metadata.
- Some customers prefer not to restore system state backups of FSMO role-holders in case the role has been reassigned since the backup was made.
- Do not put the Infrastructure master role on the same domain controller as the global catalog server. If the Infrastructure master runs on a global catalog server it stops updating object information because it does not contain any references to objects that it does not hold. This is because a global catalog server holds a partial replica of every object in the forest.
- Under
typical conditions, all five roles must be assigned to “live” domain
controllers in the forest. If a domain controller that owns a FSMO role
is taken out of service before its roles are transferred, you must
seize all roles to an appropriate and healthy domain controller. We
recommend that you only seize all roles when the other domain controller
is not returning to the domain. If it is possible, fix the broken
domain controller that is assigned the FSMO roles. You should
determine which roles are to be on which remaining domain controllers so
that all five roles are assigned to a single domain controller.
For more information about FSMO role placement, click the following
article number to view the article in the Microsoft Knowledge Base:
- Click Start, point to Programs, point to Administrative Tools, and then click Active Directory Sites and Services.
- Double-click Sites in the left pane, and then locate the appropriate site or click Default-first-site-name if no other sites are available.
- Open the Servers folder, and then click the domain controller.
- In the domain controller's folder, double-click NTDS Settings.
- On the Action menu, click Properties.
- On the General tab, view the Global Catalog check box to see if it is selected.
No comments:
Post a Comment
Note: Only a member of this blog may post a comment.