When Is the Right Time to Migrate?

When Windows Server 2003 first shipped during the Spring of 2003, many organizations wondered about the right time to migrate to the new operating system. It used to be that you waited until the first Service Pack shipped before installing any Microsoft product; however, Windows 2003 surprised a lot of organizations by being extremely reliable and actually more dependable than patched versions of Windows NT4 and Windows 2000. So, the end result decision came down to the same decision on migration to any new technologyidentify the value of migrating versus the cost and effort to migrate.

This introductory chapter notes the many features and functions built into Windows Server 2003 that have helped other organizations make the decision that Windows Server 2003 has significant value to plan a migration. Improvements in security, performance, and manageability provide benefits to organizations looking to minimize administration costs, while providing more functionality to users.

The cost and effort to migrate to Windows Server 2003 vary based on the current state of an organization's networking environment as well as the Windows Server 2003 features and functions the organization wants to implement. Some organizations begin their migration process to Windows Server 2003 by adding a Windows Server 2003 into an existing Windows NT4 or Windows 2000 network, migrating from Windows 2000 to Windows Server 2003, and migrating from Windows NT4 to Windows Server 2003.

Adding a Windows Server 2003 to an NT4 or Windows 2000 Environment

Many organizations want to add in a specific Windows Server 2003 function such as Windows Server 2003 Terminal Services, Windows Server 2003 Remote Access Services, Windows Server 2003 Media Services, or the like. Such functions can be added on Windows Server 2003 member servers in existing Windows NT4 or Windows 2000 networking environments. This allows an organization to get Windows Server 2003 application capabilities fairly quickly and easily without having to do a full migration to Windows Server 2003. In many cases, a Windows Server 2003 member server can simply be added to an existing network without ever affecting the existing network. This addition provides extremely low network impact but enables an organization to prototype and test the new technology, pilot it for a handful of users, and slowly roll out the technology to the client base as part of a regular system replacement or upgrade process.

Some organizations have replaced all their member servers to Windows Server 2003 systems over a period of weeks or months as a preparatory step to eventually migrate to a Windows Server 2003 Active Directory structure.

Migrating from Windows 2000 to Windows Server 2003

For organizations that have already migrated to Windows 2000 and the Active Directory environment, migrating to Windows Server 2003 for Active Directory functionality can provide access to several additional capabilities that require a Windows network to be running on Windows Server 2003. Some of the Windows Server 2003 technologies that require implementation of the Windows Server 2003 Active Directory include RIS for Servers, Windows Server 2003 group policy enhancements, and the full Windows Server 2003 Distributed File System.

Fortunately, organizations that have already implemented Windows 2000 or have already migrated from Windows NT4 to Windows 2000 have completed the hard part of their migration process. Effectively, Windows Server 2003 uses the same Active Directory organizational structure that was created with Windows 2000, so forests, domain trees, domains, organizational users, sites, groups, and users all transfer directly into Windows Server 2003. If the organizational structure in Windows 2000 met the needs of the organization, the migration to Windows Server 2003 is predominantly just the insertion of a Windows Server 2003 global catalog server into the existing Windows 2000 Active Directory domain to perform a global catalog update from Windows 2000 Active Directory to Windows 2003 Active Directory.

Unlike the migration process from Windows NT4 to Windows 2000, in which an organization was unable to migrate a Windows NT4 backup domain controller (BDC) to a Windows 2000 domain controller (DC), Windows Server 2003 enables an organization to migrate its Windows 2000 DCs to Windows Server 2003 DCs, thus allowing an interim mode for partial (slower) migration to Windows Server 2003.

Of course, planning, system backup, and prototype testingcovered in Chapter 17, "Migrating from Windows 2000 to Windows Server 2003"help minimize migration risks and errors and lead to a more successful migration process. However, the migration process from Windows 2000 to Windows Server 2003 is a relatively easy migration path for organizations to follow.

Many organizations choose to make changes in their Active Directory structure when they migrate from Windows 2000 to Windows Server 2003, such as changing simple domain structure or possibly even doing a complete domain rename. Windows Server 2003 provides several tools, covered in Chapter 17, that help organizations make changes to their Active Directory during their migration process. Many of these processes can be completed before migrating to Windows Server 2003, but many of them can be completed after migrating to Windows Server 2003 as well. And several of these processes are best completed during the migration of Windows Server 2003. Therefore, it is important to plan any changes and review Chapter 17 before starting a migration.

Migrating Directly from Windows NT4 to Windows Server 2003

Organizations that still have Windows NT4 in their networking environments must decide whether to migrate from Windows NT4 to Windows 2000, or to migrate directly from Windows NT4 to Windows Server 2003. Some of the deciding factors are determining what Windows Server 2003 features and functions they want and the cost and effort to migrate. As noted earlier in the section "When Is the Right Time to Migrate?", organizations do not necessarily have to migrate completely to Windows Server 2003 to get its functionality. They can choose to migrate just a couple of member servers from Windows NT4 to Windows Server 2003 without having to migrate the whole Active Directory domain structure. This can be a first step in getting Windows Server 2003 technology into their network.

If an organization has already begun its migration to Windows 2000, it might choose to shift to an implementation of future global catalog servers as Windows 2003 systems. A huge benefit of a shift from Windows 2000 Active Directory to Windows 2003 Active Directory is the ability to easily intermix global catalog servers. New global catalog servers can be Windows 2003 systems, and existing Windows 2000 global catalog servers can remain until such time as it is convenient to upgrade those servers to Windows 2003. Of course, an organization can choose to migrate completely from Windows NT4 to Windows Server 2003, and because the forest, domain, site, and other structural functions of Windows 2000 and Windows Server 2003 are identical, any planning done for a migration to Windows 2000 can be applied to an organization's decision to migrate from Windows NT4 to Windows Server 2003.

The planning, design, prototype, and migration steps to assist an organization in its migration from a Windows NT4 to a Windows Server 2003 environment are covered in Chapter 16, "Migrating from NT4 to Windows Server 2003."