IntelliMirror is a feature of Windows 2000 and Windows XP that allows for intelligent management of the user environment and user profiles. From a user's perspective, IntelliMirror is what allows their personalized menus, shortcuts, favorites, color schemes, background images and drive mappings to follow them from system to system on the network. While some of this activity is performed through standard roaming user profiles and the NTUSER.DAT file, other aspects are imbedded into group policy.
Part of how the user environment looks, acts and operates is determined by what GPOs are applied to a specific user and the client system. GPOs are applied to users and computers in the order of local, site, domain and OU. Within each of these level designations can be defined multiple GPOs with a pre-defined priority application order. Ultimately by default, the last GPO to be applied takes precedence and its configurations and settings are implemented for the affected user and system. (Remember, the use of Block Inheritance and No Override alter the default actions of GPOs.)
Each GPO is divided into two sections, a User Configuration and a Computer Configuration. When a computer first authenticates to the domain, Active Directory applies the Computer Configuration section of each assigned GPO to that system. When a user authenticates to the domain, Active Directory applies the User Configuration section of each assigned GPO to the system and the user's environment. The application of these two sections of the GPO are independent of each other. This division of function within a GPO is partly responsible for supporting IntelliMirror and roaming profiles. In other words, the User Configuration section of GPOs allows the user's customized environment to follow them around the network, as long as they log into a AD supporting client (currently Windows 2000, Windows XP and Windows 2003).
Another benefit of IntelliMirror is folder redirection. This is the ability to re-define common path name variables from local hard drive locations to network share path locations. Redirection is invisible to the user, but allows their personal data files to be accessible to them no matter what system they log into. As far as the user is concerned, they are still using local locations to store data. Centrally storing files not only makes roaming users possible and efficient, it also improves backup solutions and helps an organization comply with their written security policy.
James Michael Stewart is a partner and researcher for Itinfopros, a technology-focused writing and training organization.