Upgrading an NT 4.0 Domain Structure to Active Directory via the In-Place Upgrade Process

Upgrading an NT 4.0 domain environment to Windows Server 2003 Active Directory can be accomplished through two methods . As previously mentioned, the first method involves upgrading the domain structure in place. This method is more straightforward and easy to accomplish, but involves a greater degree of risk and does not immediately give the advantages of domain consolidation that can be achieved through the second option, which is migrating the domain accounts into a new AD structure.

This section details the steps required if the first option is chosen . The sample scenarios outlined assume a fairly simple environment, but the overall strategy can easily be ported into a more complex domain structure.

Upgrading the Windows NT4 Primary Domain Controller

Performing an in-place upgrade of a Windows NT 4.0 domain to Active Directory requires that the machine running the Primary Domain Controller (PDC) role be upgraded to Windows Server 2003. This can either be an existing domain controller, or a new one created solely for the purposes of the upgrade. To perform an in-place upgrade, insert the Windows Server 2003 installation CD-ROM into the CD-ROM drive of the PDC. Then following these steps:

1. If the server has autorun enabled, the Windows Server 2003 Setup Wizard screen appears. If it is not enabled, launch the Windows Server 2003 Setup Wizard by running the Setup.exe program from the Windows Server 2003 CD-ROM.

2. On the Welcome to Windows Server 2003 Family page, select Install Windows Server 2003 to begin upgrading the PDC to Windows Server 2003 and Active Directory. This step launches the Windows Setup Wizard.

3. On the Welcome to Windows Setup page, select the installation type of Upgrade (Recommended). This begins the upgrade of the Windows NT4 server operating system to Windows Server 2003 and Active Directory. Select Next to continue.

4. On the Licensing agreement page, use the scroll button to read the Microsoft licensing agreement. After reading the license page, select I Accept this agreement, and select Next to continue.

5. The copy of Windows Server 2003 should have a license key that came with the Windows Server 2003 CD-ROM software. Enter the 25-character product code and select Next.

The Setup Wizard begins the installation of Windows Server 2003 by copying necessary files to the PDC's hard drive. The upgrade progress can be monitored from the progress bar in the lower-left corner of the installation screen. When the Setup Wizard has completed copying files, the server automatically restarts.

Upgrading to Active Directory

When the Server Setup Wizard has completed upgrading the operating system to Windows Server 2003, the system restarts automatically and begins running the Active Directory Installation Wizard. To install Microsoft's Active Directory, follow these steps:

1. At the Welcome to the Active Directory Installation Wizard screen, select Next. This upgrades the existing Windows NT4 domain and domain security principles to Active Directory.

   NOTE

   Choosing this option maintains the existing NT 4 Domain and upgrades all domain security principles directly to Active Directory. All NT4 user accounts, domain groups, and computer accounts will automatically be upgraded into the new Active Directory domain.

   When the installation of Active Directory has completed, the next step is to review the Active Directory Users and Computers management console to ensure that all security principles have been upgraded properly.

2. Because this is an in-place upgrade, at the Create New Domain page, select the option to create a new Domain in a New Forest, and select Next.

3. As mentioned earlier, Active directory requires Domain Name System (DNS) to be installed before the Active Directory installation can continue. If the network has a DNS Server compatible with Windows Server 2003 and Active Directory, select Yes, I will configure the DNS client.

4. If there is no DNS Server on the network and this server is intended to be the first DNS Server within the new Active Directory Domain, select No, just install and configure DNS on this computer, and select Next to continue.

5. On the New Domain page, type the DNS name of the domainfor example, companyabc.com . Select Next to continue. Before completing the installation, use the scrollbar to review the server configuration summary page. Ensure that the configuration information is correct. If changes are required, use the Back button to modify the server configuration. If the installation summary is correct, click Next to continue.

6. Before choosing Finish to complete the in-place upgrade, review the Installation Wizard information. This information can identify whether any errors were experienced during setup.

NOTE

It is a good practice to review the server event and system logs upon completing any upgrade. Review each log and identify errors and warnings that can potentially affect the stability of the server that is being upgraded and cause problems with domain authentication.

Also review the Active Directory Users and Computers snap-in to ensure that all security principles have been migrated successfully to Windows Server 2003 and Active Directory.

Migrating and Replacing Backup Domain Controllers

When the PDC upgrade has been completed, the next step is to either upgrade or replace the remaining network Backup Domain Controllers (BDCs). The preferred method of replacing BDC functionality is by promoting new servers to be Windows Server 2003 domain controllers via the DCPROMO process. However, there may be some instances where existing hardware should be preserved through direct upgrades of the BDCs. In these instances, a direct upgrade can take place.

When performing an upgrade of Windows NT4 BDCs, the Active Directory Installation Wizard offers the opportunity to change a server's domain membership type or server roles. For example, an exiting NT BDC can be migrated to Windows Server 2003 and Active Directory as a member server or a domain controller.

As a rule, upgrading BDCs hosting network services such as DHCP and WINS should be considered first. By migrating vital network services, network downtime and interruption of server-to-server communications are minimized.