Transition from a Disjoint Namespace to a Contiguous Namespace
Applies To: Windows Server 2008, Windows Server 2008 R2
If your network uses a disjoint namespace and you decide to change to a contiguous namespace, there are several tasks to complete:
Configure domain member computers to use a primary DNS suffix that is the same as the Active Directory domain name
Remove unnecessary DNS suffixes from the client search lists
Remove no-longer-needed DNS suffixes from AD DS
Remove no-longer-needed permissions for Windows 2000 computers
The actual number of tasks that are required for the change depends on how much configuration was accomplished to make the disjoint namespace work. For example, if custom Domain Name System (DNS) suffix search lists were never created, there is obviously no need to remove them.
Note
If any of your servers have Service Principal Names (SPNs) that were manually configured, you may have to modify them. For information about manually configuring SPNs, see Setspn Overview (https://go.microsoft.com/fwlink/?LinkID=104232).
Configure domain member computers to use a primary DNS suffix that is the same as the Active Directory domain name
You can configure the DNS client's primary DNS suffix by using Group Policy, by manually changing the settings in the System Properties dialog box on each computer, or through a registry modification. These options are described in the following sections.
Configure primary DNS suffixes by using a GPO
On Windows Server 2003 and Windows Server 2008 servers, use a Group Policy object (GPO) to configure the primary DNS suffix for each member computer. Set the DNS Client policy for Primary DNS Suffix to the desired primary DNS suffix to match the DNS suffix of the Active Directory domain name. On Windows Server 2003–based computers, the GPO path for the Primary DNS Suffix policy setting is Computer Configuration\Administrative Templates\Network\DNS Client. On Windows Server 2008–based computers, the GPO path for the Primary DNS Suffix policy setting is Computer Configuration\Policies\Administrative Templates\Network\DNS Client. For more information, see Edit a Group Policy Object (https://go.microsoft.com/fwlink/?LinkID=108852).
Configure primary DNS suffixes by using System Properties
To change from a disjoint namespace that is created on a local computer running Windows 2000, Windows XP, or Windows Vista, complete the following procedure.
Membership in Administrators, or equivalent, is the minimum required to complete this procedure. Review details about using the appropriate accounts and group memberships at Local and Domain Default Groups (https://go.microsoft.com/fwlink/?LinkId=83477).
To configure the primary DNS suffix by using System Properties
Open the System Properties dialog box:
To open the System Properties dialog box in Windows 2000 or Windows XP, click Start, click Run, type sysdm.cpl, and then press ENTER.
To open the System Properties dialog box in Windows Vista, click Start, in Start Search type sysdm.cpl, and then press ENTER.
On the Computer Name tab, click Change, and then click More.
Verify that the value in Primary DNS suffix of this computer is the same as the Active Directory domain name.
Verify that the Change primary DNS suffix when domain membership changes check box is selected, and then click OK twice.
Click OK to confirm that the computer must be restarted, and then click Close.
When you are prompted to restart your computer, click Restart Now.
If you choose to restart your computer later, any changes that you make will take effect at that time.
Configure primary DNS suffixes by registry modification
If you use a script (or directly modify the registry) to configure the Primary DNS suffix, there are two values to modify: Domain and SyncDomainWithMembership. Both of these values are in the Parameters key under HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Tcpip. To create a contiguous namespace, enable SyncDomainWithMembership by setting its value to 1, and then enter the primary DNS suffix that is identical to the Active Directory domain for the Domain value. If the SyncDomainWithMembership value does not exist, you can create it as a REGDWORD. For more information about registry scripts, see article 264584 in the Microsoft Knowledge base (https://go.microsoft.com/fwlink/?LinkId=102370). If you configure these values in the registry, be sure to restart the computers to have the settings take effect.
Remove unnecessary DNS suffixes from the client search lists
When you change from a disjoint namespace to a contiguous namespace, there are likely to be several entries in the DNS suffix search list that clients no longer need. There may also be some different values that should be added to the DNS suffix search list. You can modify the DNS suffix search list by using Group Policy, by using Network Connections, or through registry modification. These options are described in the following sections.
Changing the DNS suffix search list by using a GPO
On Windows Server 2003 and Windows Server 2008 servers, remove any GPOs or settings that were used to create custom DNS suffix search lists that applied to the disjoint namespace. Remove the DNS Suffix Search List or configure it with the correct DNS suffixes for the contiguous namespace. On Windows Server 2003–based computers, the GPO path for the DNS Suffix Search List policy setting is Computer Configuration\Administrative Templates\Network\DNS Client. On Windows Server 2008–based computers, the GPO path for the DNS Suffix Search List policy setting is Computer Configuration\Policies\Administrative Templates\Network\DNS Client. For more information, see Edit a Group Policy Object (https://go.microsoft.com/fwlink/?LinkID=108852).
Changing the DNS suffix search list by using Network Connections
To change the DNS suffix search list by using the graphical user interface (GUI) on Windows 2000, Windows XP, or Windows Vista, complete the following procedure.
Membership in Administrators, or equivalent, is the minimum required to complete this procedure. Review details about using the appropriate accounts and group memberships at Local and Domain Default Groups (https://go.microsoft.com/fwlink/?LinkId=83477).
To change the DNS suffix search list by using Network Connections
Open Network Connections.
To open the Network Connections dialog box in Windows 2000 or Windows XP, click Start, click Run, type ncpa.cpl, and then press ENTER.
To open the Network Connections dialog box in Windows Vista, click Start, type ncpa.cpl in Start Search, and then press ENTER.
Right-click the icon that represents the computer's local network connection (Local Area Connection, by default), and then click Properties.
In This connection uses the following items, select Internet Protocol (TCP/IP), and then click Properties.
Click Advanced.
On the DNS tab, click Append these DNS suffixes (in order), and then click Add. Type the first DNS suffix that you want the client to use when it searches for single-label names (names that do not have DNS suffixes), and then click Add. Repeat this step for each successive DNS suffix that you want clients to use when they try to resolve a name.
Note
As an alternative, you can select Append primary and connection specific DNS suffixes and, as an option, also select Append parent suffixes of the primary DNS suffix, assuming that there is no longer a need for a custom list that includes other domains.
Click OK twice to confirm your changes.
Close the Local Area Connection Properties and the Network Connections dialog boxes.
Changing the DNS suffix search list by registry modification
If you want to use a script (or directly modify the registry) to configure the DNS suffix search list, you can modify the SearchList value that is located in the Parameters key under HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Tcpip. For more information about registry scripts, see article 264584 in the Microsoft Knowledge Base (https://go.microsoft.com/fwlink/?LinkId=102370).
Remove no-longer-needed DNS suffixes from AD DS
To remove permissions that may have been added to grant client computers permission to modify their primary DNS suffixes in Active Directory Domain Services (AD DS), use Active Directory Service Interfaces Editor (ADSI Edit) to complete the following procedure.
Note
ADSI Edit provides a view of every object and attribute in an Active Directory forest. You can use ADSI Edit to query, view, and edit Active Directory objects and attributes.
Membership in Domain Admins, or equivalent, is the minimum required to complete this procedure. Review details about using the appropriate accounts and group memberships at Local and Domain Default Groups (https://go.microsoft.com/fwlink/?LinkId=83477).
To remove no-longer-needed DNS suffixes from AD DS
On any domain controller in the Active Directory domain, click Start, click Run, type adsiedit.msc, and then press ENTER.
Expand Domain Naming Context (NC) to expose the directory partition that relates to the Active Directory domain for which you want to allow a disjoint namespace.
Right-click the Active Directory domain partition, and then click Properties. For example, DC=fabrikam,DC=com is the domain partition for Fabrikam.com.
In Attributes, locate and click the msDS-AllowedDNSSuffixes attribute, and then click Edit.
If there are any DNS suffixes entered in Values, select each one separately, and then click Remove.
When you have removed all the unnecessary DNS suffixes, click OK on the two open dialog boxes to confirm your changes.
Close ADSI Edit.
Remove no-longer-needed permissions for Windows 2000 computers
If AD DS was modified to allow member computers or domain controllers running Windows 2000 to update the dNSHostName and servicePrincipalName attributes of their Active Directory computer accounts, you can revert those changes by completing the following procedure.
Membership in Domain Admins, or equivalent, is the minimum required to complete this procedure. Review details about using the appropriate accounts and group memberships at Local and Domain Default Groups (https://go.microsoft.com/fwlink/?LinkId=83477).
To remove no-longer-needed permissions for Windows 2000 computers
To open Active Directory Users and Computers snap-in, click Start, click Run, type dsa.msc, and then press ENTER.
Click View, and then ensure that the Advanced Features check box is selected. If it is not selected, click Advanced Features. If the domain to which you want to allow a disjoint namespace does not appear in the console, do the following:
In the console tree, right-click Active Directory Users and Computers, and then click Connect to Domain.
In the Domain box, type the name of the Active Directory domain to which you want to allow the disjoint namespace (or use the Browse button to locate it), and then click OK.
In the console tree, right-click the object that represents the domain to which you want to allow a disjoint namespace, and then click Properties.
Right-click the domain, and then click Properties.
On the Security tab, click Advanced.
On the Permissions tab, click Add.
In Enter the object name to select, type self, and then click OK.
Configure the Apply onto box for Computer objects.
At the bottom of the Permissions box, ensure that the Allow check boxes that correspond to the Validated write to DNS host name and Validated write to service principal name permissions are cleared, and then click OK on the three open dialog boxes to confirm your changes.
Close Active Directory Users and Computers.