Windows Server 2003 feature level

In order to comply with the development of the times, many companies have upgraded the internal server Windows NT domain to a higher version, which involves the problem of AD migration. What are the advantages of a more advanced domain environment? Take the Windows 2000 AD domain as an example. It provides an extensible database schema, a domain controller for multiple primary domains, a trust relationship for automatic two-way delivery, and so on. If you migrate AD to a Windows Server 2003 domain, you can enjoy more performance and scalability, for example, it provides a logical hierarchical organization of directory information, allowing administrators to more flexibly design, deploy, and manage organizational directories. .

Domain Levels

If you have deployed Windows 2000 Active Directory, you must be familiar with the concept of domain mode. With Windows 2000 Active Directory, there are two domain modes to choose from:

Mixed mode (default): Its network configuration uses any combination of Windows 2000 and Windows NT. Windows 2000 domain controllers and Windows NT 4.0 backup domain controllers can coexist seamlessly in the same domain without any problems.

Native mode: Domain controllers in the domain can only run Windows 2000 systems. In this mode, you can enjoy some additional features, such as group nesting features and all directory service features.

Once you upgrade to Windows Server 2003, the variety of domain modes will become more abundant. In addition to the functional level similar to the two domain modes of Windows 2000, the two new domain functional levels are more representative of the advantages of Windows Server 2003 domain controllers (Note: Windows 2003 Server "domain functional level" "Domain mode" with Windows 2000 is a concept). There are four domain levels to choose from in the Windows Server 2003 AD domain:

Windows 2000 mixed domain level (default): As its name suggests, its functional level is almost identical to Windows 2000's "mixed mode". The only difference is that in addition to Windows 2000 and Windows NT, it is also suitable for Windows Server 2003 domain controllers.

Windows 2000 native domain level: Its functional level is similar to Windows 2000's "native mode", the only difference between the two is that all domain controllers in the domain can run Windows Server 2003 Or Windows 2000.

Windows Server 2003 Transition Domain Level: Allows Windows 2003 domain controllers to be mixed with Windows NT4 domain controllers, but not with Windows 2000 domain controllers.

Windows Server 2003 Domain Level: It has the highest level of functionality at the four domain levels, however, all domain controllers in the domain can only run Windows Server 2003. Enjoy the full features and functionality offered by the Windows Server 2003 AD domain.

Forest Level

After the Windows Server 2003 domain controller in the domain is deployed, you will also need to select the functional level of the forest. There are three levels to choose from:

Windows 2000 forest level (default): This forest level is similar to the default setting of Windows 2000 Domain Level. The forest functional level, which is the default state, provides the most basic forest structural features and functions.

Windows Server 2003 Transitional Forest Level: In terms of functional level, it is similar to “Windows Server 2003 domain level”. That is, you can only join Windows Server 2003 domain controllers and Windows NT domain controllers to the forest. You can enjoy the replication improvements and new properties provided by the global catalog server.

Windows Server 2003 Forest Level: This is the most functional forest configuration with all the features and functionality, including cross-forest trust. Domain controllers that are added to the forest can only run Windows Server 2003, and all domains in the forest must be set to the highest functional level "Windows Server 2003 domain level".

Which functional level is the domain of the enterprise suitable for?

Below are the advantages and disadvantages of the four domain functional levels, which you can choose based on your own needs.

Windows 2000 Mixed Domain Level: For organizations that don't completely eliminate Windows NT domain controllers, this domain level is clearly the best choice. Its biggest drawback is that since the end of 2004, Microsoft is slowly cutting back on support services for Windows NT.

Windows 2000 native domain level: If you have deployed AD migration from Windows NT to Windows 2000, then this level of functionality is clearly the best for you. Its biggest feature is that it is only suitable for upgrading from Windows NT environment to Windows 2000 Active Directory.

Windows Server 2003 Transition Domain Level: Windows Server 2003 is a very stable operating system. If you want to upgrade your Windows NT environment to Windows 2003 Active Directory in one step, you should choose this. Domain level. Its biggest feature is that Windows 2000 domain controllers are not allowed in the domain.

Windows Server 2003 Domain Level: For some small companies or enterprises, if you intend to convert the signal domain to the Windows 2003 functional level before converting the forest, then it is best to choose this domain functional level. It has only one minor flaw: requiring domain controllers in each domain to run Windows Server 2003 only throughout the forest.

Summary

Whether it's Windows 2000 Active Directory or Windows Server 2003 Active Directory, domain and forest functional levels have a lot of choice. Before making a decision, you should first select the version of the operating system that best suits your needs based on your current and future needs. Then, refer to the above introduction to the functional level to set up the domain and forest.